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date: 25 March 2017

Epidemics in Indian Country

Summary and Keywords

Few developments in human history match the demographic consequences of the arrival of Europeans in the Americas. Between 1500 and 1900 the human populations of the Americas were traBnsformed. Countless American Indians died as Europeans established themselves, and imported Africans as slaves, in the Americas. Much of the mortality came from epidemics that swept through Indian country. The historical record is full of dramatic stories of smallpox, measles, influenza, and acute contagious diseases striking American Indian communities, causing untold suffering and facilitating European conquest. Some scholars have gone so far as to invoke the irresistible power of natural selection to explain what happened. They argue that the long isolation of Native Americans from other human populations left them uniquely susceptible to the Eurasian pathogens that accompanied European explorers and settlers; nothing could have been done to prevent the inevitable decimation of American Indians. The reality, however, is more complex. Scientists have not found convincing evidence that American Indians had a genetic susceptibility to infectious diseases. Meanwhile, it is clear that the conditions of life before and after colonization could have left Indians vulnerable to a host of diseases. Many American populations had been struggling to subsist, with declining populations, before Europeans arrived; the chaos, warfare, and demoralization that accompanied colonization made things worse. Seen from this perspective, the devastating mortality was not the result of the forces of evolution and natural selection but rather stemmed from social, economic, and political forces at work during encounter and colonization. Getting the story correct is essential. American Indians in the United States, and indigenous populations worldwide, still suffer dire health inequalities. Although smallpox is gone and many of the old infections are well controlled, new diseases have risen to prominence, especially heart disease, diabetes, cancer, substance abuse, and mental illness. The stories we tell about the history of epidemics in Indian country influence the policies we pursue to alleviate them today.

Keywords: disease, race, epidemics, mortality, Columbian Exchange, virgin soil epidemics, health inequalities, health disparities, Native Americans, American Indians

Few developments in human history match the demographic consequences of the arrival of Europeans in the Americas. Between 1500 and 1800 European powers extended their influence throughout the world, bringing changes to all corners of the globe. They transformed the distribution of crops, livestock, and people on a global scale. But while the population of Asia remains largely Asian and the population of Africa remains largely African, the complexion of the Americas has changed. While recognizable American populations have survived, in most places the indigenous population of the Americas has been replaced by people of European or African ancestry. Something similar has taken place in Australia and New Zealand. The decimation of American Indian populations was one of the most dramatic demographic events of the last millennium. Its consequences persist today.

When historians have studied the demographic transformation of the Americas, they have focused on dramatic epidemics of smallpox and other infections that killed many Native Americans. They have even developed a set of theories, grounded in the logic of evolutionary biology, to explain the susceptibility of New World populations to Old World pathogens. These theories have important consequences for how we assign responsibility for the devastating mortality. If the epidemics were the inevitable result of long-standing forces of natural selection, then no one—neither the European colonizers nor the American Indians who were unable to resist—should be blamed. This account, however, does not provide an adequate explanation for the complexity of the outcomes of European arrival. While epidemics did happen, they often did not begin until after several decades of colonial encounters. While most American populations did decline, some prospered and grew in the first centuries of contact. More nuanced theories are needed, ones that ground disease and mortality in the complex social, economic, and political dynamics of colonization. Theories that acknowledge the social determinants of disease can help to understand not only the epidemics of encounter, but also the health disparities that persist in Indian country today.

Epidemic Narratives

Christopher Columbus and his crew arrived in the Caribbean in October 1492. Mortality rates among the local Carib and Taino rose quickly, a pattern repeated almost everywhere that Europeans went in the Americas. While the exact numbers remain unclear, the mortality was unprecedented and overwhelming. Smallpox, measles, influenza, and malaria (and possibly hepatitis, plague, chickenpox, and diphtheria) spread into Mexico and Peru during the 16th century, into New France and New England in the 17th century, and throughout North America and across the Pacific during the 18th, 19th, and 20th centuries. Indian populations often decreased by more than 90 percent during the first century after contact with Europeans. It is difficult to describe the horror of these epidemics in a short space. They played out over five hundred years, from Chile to Alaska, killing tens of millions of people. While a few brief narratives cannot do justice to the history, they can set the stage for a serious discussion of the causes and consequences of the mortality.

Hispaniola, the first region subjected to Spanish conquest, foretold the fate of other areas: the Arawak population decreased from as many as 400,000 in 1496 to just 125 in 1570. Peter Martyr d’Anghiera wrote one of the first histories of Spain’s exploration of the Americas. He provided abundant evidence of Spanish brutality, describing, for instance, how the Spanish hunted the Caribs and Taino with dogs and abused them so badly in gold mines that the terrorized natives destroyed their crops and killed themselves and their children. But he also described how “newe and straunge diseases . . . consumed theym lyke rotton sheepe.” The combined impact of abuse and disease was devastating. Whereas hundreds of thousands had once crowded the island, “what they are now, I abhor to rehearse.”

Disease followed the Spanish as they moved to the American mainland. Smallpox jumped from Santo Domingo to Puerto Rico and then to the Yucatán in 1519. The subsequent outbreak in Mexico contributed to the defeat of the Aztec Empire. Hernán Cortés had arrived in the Yucatán in April of that year and entered Tenochtitlán, the Aztec capital, in November. He captured the emperor, Moctezuma, and briefly used him to control the capital. By the summer of 1520, however, the Aztec rose in rebellion. Cortés and the Spanish fled the city in July. Furiously attacked on the causeways that linked the island city to the mainland, the Spanish and their Tlaxcalan allies took heavy casualties—two-thirds of them died. But even as Cortés struggled to regroup and recruit new allies, smallpox struck Tenochtitlán from October to December. Cuitlahac, Moctezuma’s brother and successor, died, as did many other Aztec nobles. When Cortés attacked the city a second time in May 1521, the weakened Aztecs could not endure the siege. They surrendered in August.

Smallpox, meanwhile, spread from the Yucatán into South America. Once again it facilitated Spanish conquest. By 1520 the Inca had assembled one of the largest empires the world had ever seen. Stretching 3,000 miles along the spine of the Andes, the empire had sophisticated roads, elaborate urban centers, and economic systems built on vertical integration across different altitudes. Smallpox reached the Inca by 1526. The emperor Huayna Capac, campaigning near Quito, caught the pestilence and died, as did his son and heir, other members of the royal family, and prominent military leaders. A war of succession broke out that fractured the empire. When Francisco Pizarro arrived, leading an expedition of just 168 Spaniards and 62 horses, and overthrew the new emperor, Atahuallpa, at Cajamarca in 1532, he was the unwitting beneficiary of a devastating epidemic. The epidemic, however, did not end Incan power. While Pizarro did decapitate the empire in 1532, he did not extend Spanish rule across all the Inca domains. Armed resistance lasted for decades. Smallpox had disrupted, but not broken, the Incan population.

While Pizarro benefited from the advance spread of smallpox, would-be conquistador Hernando de Soto might have left a trail of disease in his wake. Hoping to find empires that rivaled the riches of Mexico and Peru, de Soto led an expedition from Florida along the Gulf Coast and into what is now the southeastern United States. He found abundant Indians, but little treasure. Only half of de Soto’s expedition survived and few Spaniards ever returned to those regions. But when French explorer René-Robert Cavelier, Sieur de La Salle, led an expedition through the Southeast one hundred years later, he found the land depopulated while herds of bison, not having been hunted, roamed in large numbers. Many historians have concluded that de Soto triggered widespread mortality. If true, this was not a case of Spanish mayhem and murder: even though de Soto’s expedition disrupted many villages, its direct effects were transient. Instead, it is possible that de Soto’s expedition (and its livestock) introduced malaria and other pathogens. Epidemics, even in the absence of Europeans, assailed southeastern tribes.

Similar stories played out wherever Europeans arrived. English explorers and fishermen worked New England waters in the early 1600s, trading, raiding, and taking captives. When John Smith explored the islands of Massachusetts Bay in 1614, he found them “well inhabited with a goodly, strong and well proportioned people.” Two years later, however, an epidemic (of unknown cause) struck the coast. It extended from the mouth of the Penobscot River south through Massachusetts to the eastern shore of Narragansett Bay. Thousands of Eastern Abenaki, Massachusett, and Wampanoag Indians died. Whole villages disappeared. Richard Vines spent the winter of 1616 and 1617 with Abenaki Indians near Pemaquid, who had been weakened by war and “Plague.” Thomas Dermer, who sailed the coast in 1619, found “some ancient Plantations, not long since populous now utterly void; in other places a remnant remains, but not free of sickness.” Dermer had with him Squanto, a Wampanoag captured in 1614. He hoped to use Squanto as an interpreter to establish peaceful relations with Squanto’s village, Patuxet. But arriving there and “finding all dead,” he abandoned the plan.

When a small group of religious separatists—the Pilgrims—fled England, they arrived on the Massachusetts coast in November 1620. Finding a good harbor and some open fields, they established Plymouth. Three months later Squanto arrived at Plymouth, explained that Patuxet had been wiped out by an epidemic and that the Pilgrims had built Plymouth atop its ruins. Wherever they looked, the Pilgrims found evidence of the devastation. Their governor, William Bradford, described how the Wampanoag and Massachusett had been “abundantly wasted in the late great mortality.” Thousands had died and, “not being able to bury one another, their skulls and bones were found in many places lying still above the ground where their houses and dwelling had been, a very sad spectacle to behold.” Robert Cushman, who visited Plymouth in the summer of 1621, guessed that “the twentieth person is scarce left alive.”

News of the mortality in New England filtered back to England. When John Winthrop and the leaders of the Massachusetts Bay Company planned their migration in 1629, they wrote extensive arguments to justify their mission. Asked what right they had to settle land occupied by the Indians, they argued, in part, that “God has consumed the natives with a miraculous plague, whereby a great part of the country is left void of inhabitants.” Winthrop led 1,000 colonists to Massachusetts in 1630. Three years later smallpox struck, starting in Plymouth but quickly spreading throughout Massachusetts, along the Hudson and Mohawk Rivers, and into Quebec. Bradford left the most graphic account of the suffering: “a sorer disease cannot befall them, they fear it more than the plague. For usually they that have this disease have them in abundance, and for want of bedding and linen and other helps they fall into a lamentable condition as they lie on their hard mats, the pox breaking and mattering and running one into another, their skin cleaving by reason thereof to the mats they lie on. When they turn them, a whole side will flay off at once as it were, and they will be all of a gore blood, most fearful to behold.”

Jesuit missionaries witnessed the aftermath of this epidemic in Quebec. They arrived among the Huron in 1632. Half of the population had died within six years, from smallpox, influenza, and ill-defined fevers. The Huron connected the mortality to the French, “saying that since the coming of the French their nation was going to destruction.” The Jesuits speculated about changes in diet or the advent of alcohol, but they knew that these were not complete explanations. As Paul Le Jeune acknowledged, “I would have considerable trouble to assign a natural cause for their dying so much more frequently than they did in the past.” Although the causes were not clear, the consequences were. Hierosme Lalemant wrote, “since our arrival in these lands, those who had been the nearest to us, had happened to be the most ruined by the diseases, and that the whole villages of those who had received us now appeared utterly exterminated.”

As Euro-American settlement moved from the Atlantic coasts into the interior of North America, epidemics followed. Outbreaks of smallpox and other pathogens broke out repeatedly in the 18th century. In 1738, for instance, smallpox spread from Charlestown into the Carolina highlands, striking the Cherokee especially hard. The diseases spread through many routes. Sometimes Indians visited English towns or garrisons and unwittingly carried the viruses or bacteria back home with them; many tribes learned to avoid the English whenever disease was among them. Sometimes the diseases followed European traders as they moved through Indian country. Rumors of deliberate infection (of the English by the French, of the continental army by the British, of Indians by Europeans) were widespread. One case is well documented. At the end of the Seven Years’ War, Delaware and Shawnee warriors besieged the British garrison at Fort Pitt (now Pittsburgh). Independently of one another (since there was no way to send mail through the siege), both the British high command (Lord Jeffrey Amherst and Henry Bouquet) and the local garrison (Simeon Ecuyer and William Trent) schemed to spread smallpox among the Indians. Trent, a British trader, took two blankets and a handkerchief from smallpox patients at the fort’s hospital and gave them to Delaware negotiators. As he wrote in his journal, “I hope it will have the desired effect.” While no evidence proves definitively that this gift did spread smallpox—the siege continued vigorously for another six weeks without evidence of disease among the Delaware—there is no doubt about the intent. Evidence also exists that the diseases sometimes moved faster than the Europeans. Once inserted into Indian populations, the illnesses followed trade routes among Indian groups and reached far into North America. Smallpox, for instance, ran rampant during the American Revolution. Introduced into New Orleans, it spread north in the early 1780s, following Comanche traders up the Mississippi River and Missouri River valleys, possibly as far as the Hudson Bay, the Columbia River, and the Pacific Ocean.

The tragedies continued into the 19th and 20th centuries. Smallpox struck the Ohio River valley in 1831, spread west along the Missouri River, and caused a devastating epidemic in the Dakotas in 1837 and 1838. Estimates of total mortality range between 10,000 and 250,000. Whole villages disappeared. As one witness wrote in 1838, “no sounds but the croaking of the raven and the howling of the wolf interrupt the fearful silence.” Even the broad reaches of the Pacific Ocean afforded no protection. Hawaiians, spared extensive contact until the 19th century, saw their population decline from an estimated 800,000 in 1778 to 40,000 in 1885. Measles, exacerbated by a hurricane and famine, killed possibly one-quarter of Fijians in 1875. As recently as the 1940s and 1960s, newly constructed highways and newly arrived missionaries brought measles, whooping cough, meningitis, and other new diseases to previously isolated tribes from Alaska to Amazonia.

American Indians struggled, as all humans have struggled, to respond to the devastating epidemics. Some Indians comforted the sick and exposed themselves to contagion. Others fled, spreading the contagion far and wide. Traditional Indian remedies sometimes provided solace, but they had no power against smallpox or other pathogens. The disfigurement and demoralization caused by smallpox and other epidemics, combined with observations that Europeans sometimes remained healthy (presumably because of immunity from prior exposure), shook Indian confidence in their religious leaders and beliefs. Historians have found countless reports from the 16th through the 19th centuries of parents killing their children, of husbands killing their wives, and of individuals committing suicide to be spared the horror of the diseases. However, it is essential to recognize the variability and complexity of Indian responses to the mortality. Some groups exhibited resilience and adaptability in face of the mortality. The Cherokee, for instance, developed explanations that fit smallpox and other new diseases into existing theories involving spirits, witchcraft, taboo violations, and other upsets to the supernatural order. They performed healing rituals, tried herbal remedies, and took care to avoid British towns afflicted by smallpox.

Epidemics in Indian CountryClick to view larger

Engraving of a medicine man administering treatment to a patient, Captain Samuel Eastman, U.S. Army (1857). Courtesy of the U.S. National Library of Medicine.

Epidemics and high mortality did not end once the turbulence of encounter and colonization settled down. Instead, as new social, economic, and political arrangements took shape, American Indians continued to suffer terribly from disease. The reservation system, imposed on Indians in the United States between the 1830s and 1870s, transformed patterns of morbidity and mortality. Smallpox, measles, cholera, malaria, venereal diseases, and alcoholism remained common but were reportedly mitigated by government physicians with vaccination, fumigation, and quarantine. These problems, however, were dwarfed by tuberculosis, an ancient disease that quickly became the leading cause of death on the reservations. By the 1890s the mortality rate from tuberculosis alone on the Sioux reservations exceeded the total mortality rate—from all causes—in most major cities. Even as tuberculosis declined among the general population of the United States in the early 20th century, it remained prevalent on the reservations. During World War II, between 10 and 25 percent of Navajo recruits were sent back to the reservation because of active tuberculosis. The Navajo also had the country’s highest infant mortality rate.

Since the 1960s, Indian communities and the federal government have made substantial progress tackling the problems of disease. But substantial health inequalities persist for many leading causes of death. All-cause mortality among American Indians is 1.2 times that of the general population. Mortality is higher from chronic lung disease (1.6 times), chronic liver disease (4.7 times), diabetes (2.8 times), alcohol (6.5 times), pneumonia/influenza (1.4 times), accidental injuries (2.4 times), suicide (1.6 times), and homicide (1.8 times). The problem is not confined to the United States. Indigenous populations have health outcomes that are worse than the majority populations in every country worldwide, from Canada to the Andes and from Fiji to India and South Africa. What is the cause of these epidemics and of the health inequalities more broadly? This has been a topic of debate for more than five hundred years.

Responsibility for Epidemics

Europeans have been assigning blame and responsibility for the epidemics ever since the earliest years of encounter and colonization. Martyr, whose work became the basis of the “Black Legend,” placed the blame squarely on the Spanish. He described how forced labor in mines and famine laid the population low. Bartolomé de Las Casas, who witnessed colonization firsthand, condemned his countrymen, who behaved “like ravening beasts, killing, terrorizing, afflicting, torturing, and destroying the native peoples.” Others placed blame elsewhere. Edward Winslow, one of the leaders of Plymouth Plantation, traced “manifold diseases” among the Massachusett to their “living in swamps and other desert places.” Moravian missionary John Heckewelder, who worked on the Pennsylvania frontier in the late 18th century, emphasized the “vicious and dissolute life” produced by alcohol (which, admittedly, had been introduced by the English).

Many American Indians, aware that Europeans sometimes survived the epidemics intact, concluded that the English somehow controlled the disease. Ensenore and other local elders, who encountered the English at Roanoke in 1585 and 1586, asked the English to unleash disease against their enemies. The English declined, saying that such things were in the hands of God. When disease did then spread among those enemy tribes, the elders thanked the English for their assistance. When the French Jesuits remained healthy while the Huron died, the Huron concluded that the French “had a secret understanding with the disease (for they believe that it is a demon).” Scheming in Plymouth, Squanto used Indian fear of English disease to increase his influence as an interpreter and mediator. He told the Wampanoag that the colonists kept the plague buried in their storehouse and that they could send it forth whenever and wherever they wanted. When Hobbamock, one of Massasoit’s counselors, asked the English if this were true, they said instead that “the God of the English had it in store, and could send it as his pleasure to the destruction of his and our enemies.”

English authors often credited divine intervention, interpreting the epidemics as God’s way of clearing the land for English settlement. As Thomas Morton, who settled near Plymouth from 1622 to 1627, wrote, “the hand of God fell heavily upon them . . . the place is made so much the more fit, for the English Nation to inhabit in, and erect in it Temples to the Glory of God.” The French lacked such confidence. The Jesuits, for instance, noticed that the epidemics followed wherever they went. As Lalemant confessed, “where we were most welcome, where we baptized most people, there it was in fact where they died the most.” Shaken, Lalemant sought solace in faith: “We shall see in heaven the secret, but ever adorable, judgments of God therein.”

As the diverging demographic trajectories became ever starker over time—declining Indian populations in North America as European populations grew rapidly—many observers saw Indian demise as inevitable. In 1764, for instance, historian and Massachusetts governor Thomas Hutchinson mused about the meaning of the mortality: “Our ancestors supposed an immediate interposition of providence in the great mortality among the Indians to make room for the settlement of the English. I am not inclined to credulity, but should not we go into the contrary extreme if we were to take no notice of the extinction of this people in all parts of the continent. . . . They waste, they moulder away, and as Charlevoix says of the Indians of Canada, they disappear.” One hundred years later Congress called for an investigation of Indian depopulation. General James Carleton, who led the U.S. Army against the Navajo and other southwestern tribes, testified that the “races of the mammoths and the mastodons, and the great sloths, came and passed away: the red man of America is passing away!” Such evolutionary narratives, as described below, became increasingly popular in the 20th century.

Other writers, however, saw a different meaning in the mortality. Some did not see the epidemics and mortality as inevitable but simply as the consequence of how Indians led their lives. O. M. Chapman, who worked as a physician on the Yankton Sioux reservation in South Dakota in the early 1900s, blamed their disregard of the laws of hygiene: Sioux mortality was “the measure of their transgressions.” Over the decades that followed, physicians, government officials, and advocates held the federal government increasingly responsible for the squalid conditions on the reservations, which fueled the epidemics of tuberculosis, trachoma, and infant mortality. Many of the tribes had been confined on barren reservations without adequate resources to sustain their populations. Mired in poverty, many American Indian populations have suffered high rates of many diseases.

As the Columbian quincentenary approached in 1992, initial plans for celebration gave way to increasingly frequent accusations that Columbus had inaugurated five centuries of genocide. Regardless of whether scholars accept the claim of genocide, most now acknowledge that the epidemics that devastated Indian populations were not a coincidence. Instead, they are an important, and tragic, legacy of the arrival of Europeans in the Americas. Understanding this history, and its causes, is crucial. It is not just an academic question of getting the history right. Instead, it is both a scientific question, about understanding the causes of susceptibility to disease, and a moral question, about responsibility. Both questions are of major importance wherever health inequalities persist (i.e., everywhere).

Discussion of the Literature

Many explanations are offered for why it has been so hard for scholars to make credible judgments about who or what is responsible for the epidemics that decimated Indian populations during European encounter and colonization. One problem has been the politicization that inevitably accompanies discussions of race and inequality. Another problem arises from the many ambiguities in the historical record. Despite centuries of curiosity and decades of intensive study, uncertainty persists about the basic facts of depopulation. How large were Indian populations before the arrival of Columbus? How many died? How quickly? What were the major causes of mortality? What are the best explanations of Indian susceptibility to epidemics? It is necessary to understand the debates about these questions before returning to the question of responsibility and to consideration of the consequences of susceptibility.

The first problem is that no one knows just how many people lived in the Americas before Columbus. Few American societies kept written records. The Spanish attempted their first census of Mexico in 1568, but that compilation took place fifty years after their arrival. Early colonists sometimes estimated how many Indians had lived or died. William Bradford, for instance, guessed that during the epidemic of 1633 and 1634, “of a thousand, above nine and a half hundred of them died.” But it is impossible to know whether such guesses are reliable, and no estimates survive for many populations.

Scholars began to give this question serious attention in the 1930s. Anthropologist A. L. Kroeber compiled surviving estimates of Indian populations at the time of first contact with Europeans. He calculated a total population of 8.4 million for the Western Hemisphere, with only 900,000 living in North America. After World War II, Woodrow Borah, Sherburne Cook, and Henry Dobyns revisited this estimate. They argued that Kroeber ignored the disease-induced decline that occurred between the arrival of Europeans in the Americas and their first contact with each tribe. Estimating this loss at more than 95 percent, Dobyns proposed a pre-contact population of 112 million for the Western Hemisphere and 18 million for North America. If Dobyns is correct, then the population of the Americas in 1492 was twice that of Europe, and Tenochtitlán was one of the largest cities in the world. Recent efforts to reach a consensus have more or less split the difference between these high and low counts, for instance, estimating a population of 44 million for the Western Hemisphere and 2,360,000 for North America. Figuring this out is an important problem: understanding the deaths of 18 million Americans is a different problem from understanding the deaths of 2,360,000, in terms of both the human cost and the plausible explanations.

The second problem is the timing of the mortality. In some cases, Indian populations declined quickly. John Smith found bustling villages along the New England coast in 1614, but, five years later, Thomas Dermer found them empty. In many other cases the pace of decline is less clear. When archaeologists have looked closely, they have often found that epidemics did not begin immediately but only after decades of encounter and disruption. Columbus, for instance, arrived in the Caribbean in 1492, but evidence of epidemics in Hispaniola is not definitive until 1518. Spanish explorers reached New Mexico in 1540, but documented epidemics began only in the 1630s. Indians in what is now the southeastern United States encountered the Spanish in the 1540s. They fought and traded episodically with the Spanish, French, and English for decades, but they experienced their first major epidemics only in the 1690s, and those occurred in the chaotic aftermath of Virginia’s legalization of Indian slavery in 1692, when slave trading and raiding became particularly intense.

The Comanche provide a complex but revealing example. On the outskirts of European influence in the 18th century, they co-opted European horses and guns and transformed themselves into a regional power. Contact did bring epidemics, including smallpox in the 1780s and several other outbreaks into the 19th century. But the Comanche had considerable political power and economic resources, and their population recovered from each of these early epidemics. Starting in the 1840s, however, they began to lose land to settlers arriving from the rapidly expanding United States. By the 1860s their power was broken. In a setting marked by warfare, disrupted trade, and malnutrition, they experienced serious mortality and did not recover either their power or their health.

Understanding the details of timing is crucial. If it is true that a population decreased by 80 or 90 percent, then it matters greatly whether this happened over a few years or over a century. Epidemics that decimated populations quickly would be dramatic and unprecedented, something that would require remarkable explanations. But substantial losses over the course of a century would not require any special mechanisms. A population that loses just 2 to 3 percent annually will, by the end of a century, have experienced a 90 percent decline. If, as some archaeologists now believe, many Indian societies eked out a marginal and worsening existence prior to the arrival of Europeans, then a slight destabilization of those societies, whether by disease or by disrupted subsistence, could account for the eventual substantial drop.

The third problem is the causes of the epidemics. Without doubt the historical record is full of dramatic accounts of named epidemics, of smallpox, measles, influenza, and many others. But what percent of deaths in a society were caused by these diseases among many other possibilities? In some places warfare contributed significantly to mortality. In others it is clear that the arrival of Europeans caused major disruptions to Indian agriculture and subsistence, either by forcing Indians to transition from traditional farming practices to European ones or by allowing European livestock to overrun Indian fields. This could have caused significant starvation. Meanwhile, if conditions of Indian (and colonist) communities in the 16th into the 19th centuries were anything like those in poor, rural societies in the 20th century, then a diverse assortment of mundane diseases caused a substantial portion of overall mortality. In most developing societies, infant mortality is a leading cause of death, caused by endemic viral pneumonias and diarrheas. Adults die often from trauma, pneumonias, or bacterial infections of skin and bone. Surviving records and human remains do not allow a determination of what proportion of the mortality came from these mundane causes, which would have been present before Europeans arrived, and what proportion came from new diseases introduced by Europeans. Furthermore, mortality is only half of the problem for population decline: decreased fertility was also a significant problem. A host of factors, including physical labor, malnutrition, demoralization, and sexually transmitted infections, can compromise fertility, preventing a population from replacing its losses.

As a result of these uncertainties, when scholars try to understand the fate of American Indian populations, they cannot be certain about the size of pre-contact populations, the number of Indians who died, the pace of the mortality, or the causes of decline. The data that exist substantially underdetermine the answers that scholars seek. This void has been filled by two different narratives that reflect two fundamentally different styles of historical explanation, one biological and deterministic and the other social and contingent.

The most popular explanation traces the mortality to the inherent biological vulnerability of American Indians. This theory rose to prominence with the work of William McNeill and Alfred Crosby in the 1970s. Both men argued that the depopulation of the Americas was the inevitable result of contact between disease-experienced Old World populations and the “virgin” populations of the Americas. As Crosby defined them in 1976, “Virgin soil epidemics are those in which the populations at risk have had no previous contact with the diseases that strike them and are therefore immunologically almost defenseless.” This idea received enormous attention with Jared Diamond’s Pulitzer Prize–winning Guns, Germs, and Steel. Diamond argued: “The main killers were Old World germs to which Indians had never been exposed, and against which they therefore had neither immune nor genetic resistance.” Historians have described American Indians as “epidemiologically pristine,” “immunologically naive,” and “genetically virgin.” With “no immunity,” American Indians were “biologically defenseless.”

Such theories of immunological vulnerability apply the intuitive authority of natural selection to a challenging historical problem and efficiently explain a decisive episode in human history. As evolutionary biologist Aidan Cockburn wrote in 1967, American Indian decimation was “the typical reaction of a ‘herd’ to a pathogen not previously exposed.” Archaeologist Bruce Trigger described the depopulation as a “cruel and fantastic example of natural selection.” According to historian Francis Jennings, American Indians never had a chance: “Indeed, if there is any truth to biological distinctions between the great racial stocks of mankind, the Europeans’ capacity to resist certain diseases made them superior, in the pure Darwinian sense, to the Indians who succumbed.” Many historians since then have described how American Indians were “doomed to die.”

Virgin soil theory is used in different ways to assign responsibility for the mortality. The theories of immunological determinism can assuage Euro-American guilt over American Indian depopulation by shifting blame to long-standing evolutionary forces: the fate of the Indians was sealed, according to these theories, when sea levels rose, flooding the Bering land bridge, and isolating American Indians from Old World populations, their livestock, and their pathogens. There was nothing Europeans could have done. As one historian has written, “the unwitting spread of diseases is morally neutral.” The theory also has appeal for an opposite reason: It has been used as an argument against the supposed failure of American Indian cultures. Since the 19th century, historians had credited the easy conquests by Cortés and Pizarro to superior European military technology, strategy, and leadership. In such traditional histories, ignorant and ill-equipped Aztecs and Incas never stood a chance. But by emphasizing the power of epidemics, historians can now make an opposite claim. The Aztecs and Incas, both powerful and sophisticated societies, would have been formidable adversaries had they not been devastated by the irresistible power of smallpox. As one historian argued, “it was really European diseases and not superior European technology which defeated the Indians in the early years.”

However, over recent decades increasing evidence has accumulated that undermines the explanatory power of virgin soil theory and, instead, argues in support of the power of social, economic, and political forces to determine the outcomes of encounter. Careful work by biological anthropologists, archaeologists, and historians has elucidated the details of the mortality of specific Indian populations. While some declined dramatically, and even disappeared, others thrived after European arrival. The outcomes of encounter depended on many factors, for instance on the characteristics of pre-contact American Indian populations (e.g., size, density, social structure, nutritional status) and the patterns of European colonization (e.g., frequency and magnitude of contact, invasiveness of European colonial regime). In Mexico and Peru, for instance, Indian mortality was higher in the tropical lowlands than in the temperate highlands. It also varied within those regions, depending on the intensity of Spanish colonialism and the nature of the economic regime they created. Imposition of mining was more disruptive than agriculture, while forcing natives to labor in cotton mills (while leaving basic subsistence activities intact) did the least damage of all.

It has not been difficult to explain why the details of encounter influence the magnitude of mortality. Any factor that causes mental or physical stress—displacement, warfare, drought, destruction of crops, soil depletion, overwork, slavery, malnutrition, social and economic chaos—can increase susceptibility to disease. Natural disasters, including droughts, crop failures, earthquakes, volcanoes, and hurricanes all contributed to the suffering. These same social and environmental factors also decrease fertility, preventing a population from replacing its losses. Many Indian societies had marginal nutritional status before contact. Baseline malnutrition might have left American Indians vulnerable, at the outset, to European diseases. When the conditions of colonization disrupted subsistence, the situation only grew worse. There may have been nothing inherently different about the disease experience of American Indians: All human populations have suffered devastating epidemics. What was unique for Indians was European colonization. This added burden may have prevented American populations from recovering from the epidemics.

The historical record, of epidemic after epidemic, suggests that high mortality must have been a likely consequence of encounter. But it does not mean that mortality was the inevitable result of inherent immunological vulnerability. While it is possible that Indians’ lack of prior exposure left them vulnerable in some way to European pathogens, the specific contribution of such genetic factors is probably unknowable. Moreover, theories of immunological determinism reduce the depopulation of the Americas to an inevitable encounter between powerful diseases and vulnerable peoples. This does not match the contingency revealed in historical and archaeological records. Research has now shown that the fates of individual populations depended on contingent factors of their physical, economic, social, and political environments. It could well be that the epidemics among American Indians, despite their unusual severity, were caused by the same forces of poverty, malnutrition, social stress, dislocation, economic inequality, and environmental vulnerability that cause epidemics in all other times and places. The history is not one of populations born vulnerable but of populations made vulnerable.

It is, of course, possible that both sets of factors contributed. Epidemics—whatever their cause—would have exacerbated the stresses of encounter and colonization, weakening populations, disrupting subsistence, and further increasing their susceptibility to disease. What remains in doubt is the relative contribution of social, cultural, environmental, and genetic forces. Did the high mortality seen in most populations reflect a shared genetic variability, whose final intensity was shaped by social variables? Or does it reflect a shared social experience, of preexisting nutritional stress exacerbated by the widespread chaos of encounter and colonization? Both positions are defensible.

As a result, anyone who studies epidemics in Indian country must grapple with two competing narratives. Each has a compelling logical structure, whether of evolutionary biology or of social contingency. Each has well-documented exemplars, of tribes who collapsed without ever having seen Europeans and of tribes that escaped disease until worn down by oppressive European colonial regimes. Readers must decide which evidence and which narratives are more persuasive. As they do, they must be wary about making unwarranted assumptions. Just because virgin soil theory is plausible does not mean that it is true. Instead, we must acknowledge the full complexity of Native American demographic history, distinguish evidence and speculation, and understand why clear answers to vital questions remain elusive.

This is not just a question of getting the facts of history correct. Instead, the stories we tell about the past have consequences today. They shape how we think about health inequalities not just for American Indians, but also for all populations worldwide. If historians attribute depopulation to irresistible genetic and microbial forces, they risk being interpreted as supporting racial theories of historical development. Explanations grounded in contingency, in contrast, acknowledge the multiple ways in which social forces and human agency influence patterns of health and disease. Given the persistence of substantial health inequalities between indigenous populations and other groups worldwide, the stakes are huge. The explanations that historians endorse have profound consequences for how responsibility for past mortality is understood and for who will be held responsible for alleviating the inequalities that persist today.

Primary Sources

Very few records preserve Indian perspectives on the epidemics of encounter. One classic is Broken Spears: The Aztec Account of the Conquest of Mexico, edited by Miguel Leon-Portilla. The “winter counts” of some Sioux groups, painted on buffalo skins, record epidemics, possibly of measles or smallpox. And the oral history traditions of many tribes contain stories about the disease and suffering that occurred after the arrival of Europeans. Many mediated sources also exist: European writers often described what the Indians said and did about the epidemics (e.g., the conversion narratives collected by John Eliot and Thomas Mayhew in Massachusetts or various diplomatic records left by government officials). However, it is not clear how accurate such accounts are since they were presumably written to serve the purposes of their European authors and not to record authentic Indian perspectives.

The records of the European groups, in contrast, are voluminous. The Spanish Empire, which was the largest of the colonial empires, left a trove of published (and often reprinted) accounts as well as extensive archival collections in Seville as well as in Mexico City, Lima, and other colonial cities. Surviving sources range from conquistador’s accounts (e.g., Hernán Cortés, Letters from Mexico) to the records of hospitals established by the Spanish in Mexico City. Historians have mined the most famous sources, but many promising records remain underutilized. Some of these sources need to be used with care because the most accessible versions (e.g., compilations, translations) sometimes differ significantly from the original source. Robert McCaa provides an excellent discussion of this problem in a 1995 article in the Journal of Interdisciplinary History (“Spanish and Nahautl Views on Smallpox and Demographic Catastrophe in Mexico”). The Portuguese Empire, based in Brazil, also produced copious accounts and archival records. These collections, like the Spanish records, have not yet been thoroughly mined by historians.

Although the French had a much smaller presence, many of the 17th-century records—mostly written by Jesuit missionaries—have been conveniently collected and republished in The Jesuit Relations and Allied Documents, edited by Reuben Gold Thwaites. By the 18th and 19th centuries the most detailed Canadian sources are in English. The records of the Hudson Bay Company have been especially valuable for documenting the spread and mortality of smallpox and other named epidemics throughout the northern interior of North America.

Early Dutch sources were compiled a century ago and published as Narratives of New Netherland, edited by J. Franklin Jameson. A new translation, led by Charles T. Gehring, is in the works. Dutch explorers were also active in South America, and their accounts describe epidemics in the Amazon Basin.

English sources—more extensive than Dutch, French, or Swedish but less extensive than Spanish—have been studied most closely. These include the accounts of early explorers (e.g., Thomas Hariot, A Brief and True Report of the New Found Land of Virginia), journals of prominent colonists (e.g., The Journal of John Winthrop, 1630–1649), and many others. Since the English did not establish hospitals until the 18th century, no institutional archive exists that focuses on disease, and since Indians were not as integrated into English society as they were in New Spain, English government documents contain fewer reports about epidemics and mortality. However, discussions of Indian epidemics, and what to do about (or with) them, can be found in nearly every surviving source from the early colonial period. Over the 18th and 19th centuries the number and range of surviving sources increases dramatically, especially in the records of the federal government (first in the War Department and then in the Department of the Interior, especially what would become the Bureau of Indian Affairs).

Many of the sources—English, French, Indian, and others—have been collected in an online repository, Early Encounters in North America: Peoples, Cultures, and the Environment. With more than 100,000 pages by nearly 1,500 authors, this web resource is a highly valuable collection of primary sources.

Further Reading

Alchon, Suzanne. A Pest in the Land: New World Epidemics in a Global Perspective. Albuquerque: University of New Mexico Press, 2003.Find this resource:

Crosby, Alfred W. The Columbian Exchange: Biological and Cultural Consequences of 1492. Westport, CT: Greenwood, 1972.Find this resource:

———. “Virgin Soil Epidemics as a Factor in the Aboriginal Depopulation in America.” William and Mary Quarterly 33 (April 1976): 289–299.Find this resource:

Diamond, Jared Guns, Germs, and Steel: The Fates of Human Societies. New York: W. W. Norton, 1997.Find this resource:

Dobyns, Henry F. Their Numbers Become Thinned: Native American Population Dynamics in Eastern North America. Knoxville: University of Tennessee Press, 1983.Find this resource:

Fenn, Elizabeth A. Pox Americana: The Great Smallpox Epidemic of 1775–82. New York: Hill & Wang, 2003.Find this resource:

Henige, David Numbers from Nowhere: The American Indian Contact Population Debate. Norman: University of Oklahoma Press, 1998.Find this resource:

Jones, David S. “Virgin Soils Revisited.” William and Mary Quarterly 60 (October 2003): 703–742.Find this resource:

———. Rationalizing Epidemics: Meanings and Uses of American Indian Mortality since 1600. Cambridge, MA: Harvard University Press, 2004.Find this resource:

Kelton, Paul. Epidemics & Enslavement: Biological Catastrophe in the Native Southeast, 1492–1715. Lincoln: University of Nebraska Press, 2007.Find this resource:

Kunitz, Stephen J. Disease and Social Diversity: The European Impact on the Health of Non-Europeans. New York: Oxford University Press, 1994.Find this resource:

Livi Bacci, Massimo. Conquest: The Destruction of the American Indios. Translated by Carl Ipsen. Cambridge, UK: Polity, 2008.Find this resource: