Contagion Historical Views of Diseases and Epidemics

The Boston Smallpox Epidemic, 1721

Between April and December 1721, 5,889 Bostonians had smallpox, and 844 died of it. October was the worst month, with 411 deaths. Smallpox caused more than three–quarters of all deaths in Boston that year.

Colman, Benjamin. A narrative of the method and success of inoculating the small-pox in New England. EC7 A100 722c. Houghton Library, Harvard University, Cambridge, Mass. [Title Page]

Smallpox is a very old disease, with evidence for its presence going back centuries. In Europe and the United States, bouts of smallpox were considered to be almost inevitable, and the disease was greatly feared. Epidemics could kill 30% of those infected and cause permanent disfiguration in the rest. In some populations, the impact was even more severe: After being introduced by 16th-century Europeans, smallpox is said to have killed most of the indigenous population of North America.


It was widely known that survivors of smallpox were immune to later occurrences of the disease. This led to the practice of inoculation–the deliberate introduction of living smallpox virus to cause a mild (it was to be hoped) case of the disease that would provide immunity. The practice of inoculation developed in many parts of the world, often as part of a system of folk medicine.

By the mid–1700s, China, India, and parts of Africa had probably practiced inoculation for centuries; laypeople in Europe probably had been doing so for generations as well. The practice was discussed in the Royal Society in 1699 and published in the Philosophical Transactions of the Royal Society in 1714 and 1716. Inoculation was further popularized among England’s elites after Lady Mary Montague’s 1718 publication of her letters, which related her observation of the procedure in Turkey.

Boston 1721

Despite the promise that inoculation seemed to hold for controlling smallpox, the Boston smallpox epidemic of 1721 is known for the passionate controversy over inoculation that erupted in the city, most visibly between Reverend Cotton Mather and Boston physician William Douglass. Mather had learned about the procedure from the Philosophical Transactions of the Royal Society and from one of his enslaved servants. After inoculating his own son, Mather advocated strongly for inoculation as the Boston epidemic grew.

Most Boston physicians, as well as the general public, however, argued with equal passion against inoculation on the grounds that it could spread the disease rather than prevent it; that it could cause a fatal case of smallpox in the inoculated subject; and that it could make the subject susceptible to other diseases. These fears were not groundless: inoculation could indeed cause fatal cases of smallpox, and because inoculation proceeded by the direct transmission of bodily matter from one person to another through an open cut, diseases like syphilis could be spread by the procedure as well. Feelings ran high, and one protester threw a lighted bomb through the window of Mather’s house.

Douglass, with his medical degree from Edinburgh, was Boston’s only university–trained doctor. He argued that Mather’s inoculations undermined legitimate medical authority and contended that inoculation without regulated quarantine of the inoculated afterwards would only make the epidemic worse. Given that Mather was neither carrying out his inoculations in an organized manner nor isolating newly inoculated patients appropriately, Douglass’s criticism was legitimate.

Only one physician, Zabdiel Boylston, publicly supported Mather’s efforts after trying out the procedure on his own son and two enslaved people. Boylston would eventually inoculate around 180 people, including many prominent Bostonians.

God’s Will?

The religious debate was also important. Mather, who had lost his wife and three youngest children in a measles epidemic, argued that inoculation was a gift from God. Those opposed to inoculation argued that epidemic diseases afflicted the people for a divine reason, and that to attempt to prevent them was to oppose God’s will. Others argued that inoculation, with its roots in Africa, Asia, and the Middle East, was a heathen practice not suitable for Christians.

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The following sources were used in writing this page.

  • Blake, John B. “The Inoculation Controversy in Boston: 1721–1722.” The New England Quarterly 25, no. 4 (1952): 489–506.
  • Blake, John B. Public Health in the Town of Boston, 1630–1822. Cambridge: Harvard University Press, 1959.
  • Carrell, Jennifer Lee. The Speckled Monster: A Historical Tale of Battling Smallpox. New York: Dutton, 2003.
  • Durton, John D. “The Awful Judgements of God upon the Land: Smallpox in Colonial Cambridge, Massachusetts.” The New England Quarterly. 74, no. 3 (2001): 495–506.
  • Gronim, Sarah Stidstone. “Imagining Inoculation: Smallpox, the Body, and Social Relations of Healing in the Eighteenth Century.” Bulletin of the History of Medicine, 80, (2006): 247–268.
  • Herbert, Eugenia W. “Smallpox Inoculation in Africa.” The Journal of African History, 16, no. 4 (1975): 539–559.
  • Miller, Perry. The New England Mind: From Colony to Province. Cambridge: Harvard University Press, 1953.
  • Minardi, Margot. “The Boston Inoculation Controversy of 1721–1722: An Incident in the History of Race.” The William and Mary Quarterly. (2004): 47–76.
  • Van De Wetering, Maxine. “A Reconsideration of the Inoculation Controversy.” The New England Quarterly. 58, no. 1 (1985): 46–67.
  • Winslow, Ola Elizabeth. A Destroying Angel: The Conquest of Smallpox in Colonial Boston. Boston: Houghton Mifflin Company, 1974.