Traditional Indian remedies against illness—sweats, cold baths, and medicinal herbs—were ineffective against smallpox. Indeed, many efforts at healing only seemed to hasten death. In Europe, at its worst, smallpox killed about one out of three people it infected; in the Americas the death rate was higher than 50 percent and in many cases approached 90 to 95 percent.
Epidemiologists generally agree that smallpox is the cruelest disease ever to afflict the human race. In the century before it was eradicated in the 1970s, it killed more than half a billion people and left millions of others horribly scarred and blind. It inflicts unbearable suffering, both physical and psychological. It usually starts like the flu, with headache, fever, and body aches; and then it breaks out as a sore throat that soon spreads into a body rash. As the disease develops over the subsequent week, the victim often experiences frightful hallucinatory dreams and is racked by a mysterious sensation of existential horror. The rash turns into spots that swell into papules, and then fluid-filled pustules that cover the entire body, including the soles of the feet. These pustules sometimes merge, and the outer layer of skin becomes detached from the body. In the most deadly variety of smallpox, the hemorrhagic form, called the bloody pox or black pox, the skin turns a deep purple or takes on a charred look, and comes off in sheets. The victim often “bleeds out,” blood pouring from every orifice in the body. It is extremely contagious. Unlike most other viruses, smallpox can survive and remain virulent for months or years outside the body in clothing, blankets, and sickrooms.
The Indians were in abject terror of it. It was like nothing they had ever experienced before. The history of the Conquest contains many Spanish eyewitness accounts attesting to the horrors of the pandemic. “It was a dreadful illness,” wrote one friar, “and many people died of it. No one could walk; they could only lie stretched out on their beds. No one could move, not even able to turn their heads. One could not lie face down, or lie on the back, nor turn from one side to another. When they did move, they screamed in pain… Many died from it, but many died only of hunger. There were deaths from starvation, for they had no one left to care for them.”
These epidemics of disease weakened Indian military resistance, and in many instances it aided the Spanish in their conquest. But overall, the Spanish (and Columbus personally) were deeply dismayed by the vast die-offs; the deaths of so many Indians interfered with their slaving businesses, killed their servants, and emptied their plantations and mines of forced labor. When smallpox arrived, the Indians often responded with panic and flight, abandoning towns and cities, leaving behind the sick and dead. And while the Spanish were less susceptible to these epidemics, they were not immune, and many also died in the general conflagration.
Epidemics cleared out huge swaths of the New World even before Europeans got there. There are numerous accounts of European explorers arriving in a village for the first time, only to find everyone dead, the houses full of rotting, pustule-covered corpses.
Historians once marveled at how Cortés, with his army of five hundred soldiers, defeated the Aztec empire of over a million people. Various ideas have been advanced: that the Spanish had crucial technological advantages in horses, swords, crossbows, cannon, and armor; that the Spanish had superior tactics honed by centuries of fighting the Moors; that the Indians held back, fearful the Spanish were gods; and that the Aztecs’ subjugation and misrule of surrounding chiefdoms had created conditions ripe for revolt. All this is true. But the real conquistador was smallpox. Cortés and his troops occupied the Aztec capital city of Tenochtitlan (the future Mexico City) in 1519, but this cannot be counted as a conquest: The uneasy Aztec emperor, Moctezuma, invited Cortés into the city, unsure if he were god or man. Eight months later, after Moctezuma was murdered under murky circumstances (perhaps by the Spanish, perhaps by his own people), the Indians rose up and handily drove the Spanish from the city, in the so-called Noche Triste, the “Night of Sorrows.” In this crushing rout, many Spanish soldiers either were killed or drowned as they fled the island on which the city was built, because they had overloaded their pockets with gold. After their flight, the Spanish encamped in Tlaxcala, thirty miles east of Tenochtitlan, licking their wounds and wondering what to do next. At that moment, smallpox invaded the Valley of Mexico.
“When the Christians were exhausted from war,” one friar wrote, “God saw fit to send the Indians smallpox.” In sixty days, smallpox carried off at least half of the inhabitants of Tenochtitlan, which had a precontact population of 300,000 or more. Smallpox also killed the very capable successor to Moctezuma, the emperor Cuitláhuac, who in his brief, forty-day rule had swiftly been building military alliances that, had he survived, would very likely have repelled Cortés. But with at least half the population dead and the city and surrounding countryside engulfed in chaos by the epidemic, Cortés was able to retake the city in 1521. The worst effect of smallpox was the complete demoralization of the Indians: They saw clearly that disease decimated them while largely sparing the Spanish, and they concluded they had been cursed and rejected by their gods, who had shifted to the side of the Spanish. As the Spanish marched into the city, one observer wrote, “The streets were so filled with dead and sick people, that our men walked over nothing but bodies.”
At the same time that smallpox was ravaging Mexico, it burned southward into the Maya realm before the Spanish arrived. While the Maya cities were no longer inhabited, the Maya people were spread out over the region and were still known for their fierceness and military prowess. The contagion paved the way for the conquest of Guatemala four years later by one of Cortés’s captains.