Biological Warfare in
Eighteenth-Century North
America: Beyond Jeffery Amherst

Elizabeth A. Fenn

Did he or didn't he? For generations, the Amherst-smallpox blanket episode has elicited animated debate both within and beyond academic circles. In books, journals, and now in internet discussion groups, historians, folklorists, and lay people have argued the nuances of the case. Some have contended that at Gen. Jeffery Amherst's orders, British subordinates at Fort Pitt in 1763 did indeed infect local Indians with items taken from a nearby smallpox hospital. Others have argued that they did not, that the British lacked the knowledge, the ability, or the desire to do so. Still others have claimed that regardless of intent, the timing is wrong, that the Indians around Fort Pitt came down with smallpox well before the damning exchange of letters between Jeffery Amherst and his subordinate Henry Bouquet, and that in fact they were sick even before they received "two Blankets and an Handkerchief" out of the post's smallpox hospital. Finally, and perhaps predictably, a recent article has focused on the incident's genesis as a highly mutable cross-cultural legend that reflects deep anxieties about encounters with the "other."1 1
     What follows is not an attempt to condemn or exonerate Jeffery Amherst. The man's documentary record speaks loudly enough regarding his character, if not regarding his ultimate culpability for the smallpox that struck Indians near Fort Pitt in 1763 and 1764. Nor is this essay an exhaustive accounting of all the accusations and incidents of biological warfare in late-eighteenth-century North America. It is, however, an attempt to broaden the debate and to place it in context.2 Our preoccupation with Amherst has kept us from recognizing that accusations of what we now call biological warfare—the military use of smallpox in particular—arose frequently in eighteenth-century America. Native Americans, moreover, were not the only accusers. By the second half of the century, many of the combatants in America's wars of empire had the knowledge and technology to attempt biological warfare with the smallpox virus. Many also adhered to a code of ethics that did not constrain them from doing so. Seen in this light, the Amherst affair becomes not so much an aberration as part of a larger continuum in which accusations and discussions of biological warfare were common, and actual incidents may have occurred more frequently than scholars have previously acknowledged. 2

Fort Pitt, 1763

The most famous "smallpox blanket" incident in American history took place in the midst of Pontiac's Rebellion in 1763. In May and June of that year, a loose confederation of tribes inspired by the Ottawa war leader Pontiac launched attacks on British-held posts throughout the Great Lakes and Midwest. On May 29, 1763, they began a siege of Fort Pitt, located in western Pennsylvania at the confluence of the Allegheny and Monongahela rivers. The officer in charge at Fort Pitt was the Swiss-born captain Simeon Ecuyer. On June 16, 1763, Ecuyer reported to Col. Henry Bouquet at Philadelphia that the frontier outpost's situation had taken a turn for the worse. Local Indians had escalated the hostilities, burning nearby houses and attempting to lure Ecuyer into an engagement beyond the walls of the well-protected post, where traders and colonists, interlopers on Indian lands, had taken refuge. "We are so crowded in the fort that I fear disease," wrote Ecuyer, "for in spite of all my care I cannot keep the place as clean as I should like; moreover, the small pox is among us. For this reason I have had a hospital built under the bridge beyond musket-fire." Henry Bouquet, in a letter dated June 23, passed the news on to Jeffery Amherst, the British commander in chief, at New York. "Fort Pitt is in good State of Defence against all attempts from Savages," Bouquet reported, but "Unluckily the small Pox has broken out in the Garrison."3 By June 16, then, from sources unknown, smallpox had established itself at Fort Pitt. It is likely that Amherst knew of the situation by the end of June. 3
     But it was not Amherst, apparently, who first proposed the use of smallpox against the Delaware, Shawnee, and Mingo Indians surrounding Fort Pitt. Nor was it Amherst who executed the scheme. While the actual provenance of the plan remains unclear, a brief description of the deed itself appears in the diary of William Trent, a trader and land speculator with ties to the more prominent George Croghan. On June 23, the very day that Bouquet penned his letter to Amherst from Philadelphia, Trent reported that two Delaware dignitaries, Turtle's Heart and Mamaltee, visited Fort Pitt late at night and asked to speak with post officials. A conference took place the following day, June 24, in which the Indians urged the British to abandon the fort, and the British, for their part, refused. The parleys came to a close, and the Indians asked for "a little Provisions and Liquor, to carry us Home." The British obliged their request. "Out of our regard to them," wrote William Trent, "we gave them two Blankets and an Handkerchief out of the Small Pox Hospital. I hope it will have the desired effect."4 He does not mention who conceived the plan, and he likewise does not mention who carried it out, but Fort Pitt account books make it clear that the British military both sanctioned and paid for the deed. The records for June 1763 include this invoice submitted by Levy, Trent and Company: 4

To Sundries got to Replace in kind those which were taken from people in the Hospital to Convey the Smallpox to the Indians Vizt:
2 Blankets @ 20/ £299 099 0
1 Silk Handkerchef 10/
& 1 linnen do: 3/6 099 1399 6

Captain Ecuyer certified that the items "were had for the uses above mentioned," and Gen. Thomas Gage ultimately approved the invoice for payment, endorsing it with a comment and his signature.5  
     Had Jeffery Amherst known of these actions, he certainly would have approved. From the safety of his New York headquarters, he laid forth his own strategy for biological warfare in early July, prompted no doubt by Bouquet's letter of June 23 informing him that smallpox had broken out at the Monongahela post. In an undated memorandum that is apparently a postscript to a letter of July 7, 1763, Amherst proposed the following to Bouquet: "Could it not be contrived to Send the Small Pox among those Disaffected Tribes of Indians? We must, on this occasion, Use Every Stratagem in our power to Reduce them." Bouquet, now at Carlisle en route to Fort Pitt with reinforcements, replied on July 13, also in postscript: "I will try to inocculate the Indians by means of Blankets that may fall in their hands, taking care however not to get the disease myself." To this Amherst responded approvingly on July 16. "You will Do well to try to Innoculate the Indians by means of Blanketts, as well as to try Every other method that can serve to Extirpate this Execreble Race."6 Unbeknownst to both Bouquet and his commander in chief, their subordinates at Fort Pitt had already conceived and executed the very plan proposed. If the garrison at Fort Pitt perpetrated a second, later act of biological warfare at Amherst's behest, the documents currently available make no mention of it. 5
     What the documents do show, however, is that smallpox struck hard among the Indians around Fort Pitt in the spring and summer of 1763. On April 14, 1764, a man named Gershom Hicks arrived at the British post, having escaped from the Shawnee and Delaware Indians who had held him captive since May 1763. In a deposition taken the day of his arrival, Hicks reported "that the Small pox has been very general & raging amongst the Indians since last spring and that 30 or 40 Mingoes, as many Delawares and some Shawneese Died all of the Small pox since that time, that it still continues amongst them." Five months later, in September 1764, the epidemic continued to wreak havoc among the Shawnees. "Ye poor Rascals are Dieing very fast with ye small pox," reported Col. Andrew Lewis from Virginia's Blue Ridge Mountains; "they can make but Lettle Resistance and when Routed must parish in great Numbers by ye Disordere." Accounts of the plague continued to circulate as late as 1765, when Killibuck, a prominent Delaware leader, told the Indian agent William Johnson of the destruction it had wrought. "The Shawanes lost in three Months time 149 Men besides Women & Children by Sickness above a year ago," Killibuck reported; "also many of them dyed last Summer of the Small Pox, as did Several of their Nation." As the historian Michael McConnell has pointed out, it is possible and perhaps likely that the epidemic stemmed from multiple sources of infection. John M'Cullough, a fifteen-year-old captive among the Indians, reported that the disease took hold after an attack on some settlers sick with the smallpox along central Pennsylvania's Juniata River. The timing, however, is uncanny: the eruption of epidemic smallpox in the Ohio country coincided closely with the distribution of infected articles by individuals at Fort Pitt.7 While blame for this outbreak cannot be placed squarely in the British camp, the circumstantial evidence is nevertheless suggestive. 6
     Usually treated as an isolated anomaly, the Fort Pitt episode itself points to the possibility that biological warfare was not as rare as it might seem. It is conceivable, of course, that when Fort Pitt personnel gave infected articles to their Delaware visitors on June 24, 1763, they acted on some earlier communication from Amherst that does not survive today.8 The sequence of events, however, makes it more likely that Amherst and Fort Pitt authorities conceived of the idea independently. In each case, the availability of contagious material (thanks to the smallpox epidemic at the post itself) seems to have triggered the plan of infection. Ecuyer reported the outbreak at Fort Pitt on June 16, and the attempt to communicate the disease took place eight days later. Amherst learned of the outbreak in Bouquet's letter of June 23, and the commander in chief proposed his own scheme on July 7. The fact that a single wartime outbreak could prompt two independent plans of contagion suggests that the Fort Pitt incident may not have been an anomaly. Evidence from other fields of battle indicates that in the minds of many, smallpox had an established, if irregular, place in late-eighteenth-century warfare. 7


Elizabeth A. Fenn is an assistant professor of history at George Washington University. This essay received the Louis Pelzer Memorial Award for 1999.

I am grateful to John Mack Faragher for suggesting that I write this article and for commenting on an early draft. Wayne Lee shared important references with me and helped me locate the essay in the field of military history. Members of the Michigan Colonial Studies Seminar and the Michigan History of Medicine and Health Colloquium provided helpful critiques of an earlier version, as did the Faculty and Graduate Student Seminar at the University of South Florida department of history. Further insights, references, and assistance came from Holly Brewer, Erika Bsumek, John Dann, Pat Galloway, Don Higginbotham, Margaret Humphreys, Paige Raibmon, Neal Salisbury, Mark Wheelis, and Peter Wood, as well as the editors and anonymous reviewers of the Journal of American History. Financial support came from the Charlotte W. Newcombe Foundation.

1 William Trent, "William Trent's Journal at Fort Pitt, 1763," ed. A. T. Volwiler, Mississippi Valley Historical Review, 11 (Dec. 1924), 400. For an excellent appraisal of the Fort Pitt episode that places it in the context of the larger and more complicated struggle for control of the Ohio Valley, see Michael N. McConnell, A Country Between: The Upper Ohio Valley and Its Peoples, 1724-1774 (Lincoln, 1992), 194-96. For an example of an Internet discussion devoted to biological warfare and smallpox, see the h-oieahc discussion log for April 1995, available at For the contention that the attempt at biological warfare was "unquestionably effective at Fort Pitt," see Francis Jennings, Empire of Fortune: Crowns, Colonies, & Tribes in the Seven Years War in America (New York, 1990), 447-48, 447n26. On the issue of timing, see Bernhard Knollenberg, "General Amherst and Germ Warfare," Mississippi Valley Historical Review, 41 (Dec. 1954), 489-94; Bernhard Knollenberg to editor, "Communications," Mississippi Valley Historical Review, 41 (March 1955), 762; and Donald H. Kent, to editor, ibid., 762-63. For a cross-cultural analysis of the incident's place in a pantheon of other such "legends," see Adrienne Mayor, "The Nessus Shirt in the New World: Smallpox Blankets in History and Legend," Journal of American Folklore, 108 (Winter 1995), 54-77.

2 A thorough appraisal of the use of biological warfare in the prescientific era can be found in Mark Wheelis, "Biological Warfare before 1914," in Biological and Toxin Weapons: Research, Development, and Use from the Middle Ages to 1945, ed. Erhard Geissler and John van Courtland Moon (Oxford, 1999), 8-34.

3 For a summary of the documentation of this incident, see Knollenberg, "General Amherst and Germ Warfare," 489-94; and Kent to editor, "Communications," 762-63. While my conclusions differ from Knollenberg's, much of the evidence consulted is the same. Simeon Ecuyer to Henry Bouquet, June 16, 1763 [translation], in The Papers of Col. Henry Bouquet, ed. Sylvester K. Stevens and Donald H. Kent (30 series, Harrisburg, 1940-1943), series 21649, part 1, p. 153. The series numbers cited here correspond to the Additional Manuscripts classification of the British Museum, London, where the original manuscripts are stored. These numbers are also printed in the published version of the papers. Because libraries holding the published Papers of Col. Henry Bouquet have bound them in a variety of configurations, I have cited the series number rather than the volume number to make the precise location of each reference clear. Bouquet to Jeffery Amherst, June 23, 1763, ibid., ser. 21634, p. 196.

4 Alexander McKee gives the name of the second Delaware representative as "Maumaidtee." Alexander McKee, Report of Speeches of the Delaware Indians [addressed to George Croghan], Fort Pitt, June 24, 25, 1763, in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21655, p. 210; Trent, "William Trent's Journal at Fort Pitt," ed. Volwiler, 400.

5 Levy, Trent and Company: Account against the Crown, Aug. 13, 1763, in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21654, pp. 218-19. While the account was submitted for payment in August, the items in it are all listed under the date "1763 June." As Mark Wheelis has pointed out, readers should note that William Trent refers to a single handkerchief in his journal, while the invoice is for two: one silk, one linen. Wheelis, "Biological Warfare before 1914," 23n73.

6 Memorandum by Sir Jeffery Amherst, [July 7, 1763], in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21634, p. 161. (Stevens and Kent tentatively assign the undated document the date of May 4, 1763, but this is apparently an error.) Bouquet to Amherst, Aug. 11, 1763, ibid., 243; Bouquet to Amherst, July 13, 1763, in Jeffery Amherst, Official Papers, 1740-1783 (microfilm, 202 reels, World Microfilms Publications, 1979), reel 32, frame 305. The published typescript of this last document deviates in important ways from the original. See Bouquet to Amherst, July 13, 1763, in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21634, p. 214. For the July 16 letter, see Amherst to Bouquet, July 16, 1763, in Amherst, Official Papers, reel 33, frame 114. Here the deviations in the published typescript are insignificant. See Memorandum by Sir Jeffery Amherst, [July 16, 1763], in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21634, p. 161. (Stevens and Kent tentatively assign the date of May 4, 1763, to this document as well, but this is incorrect.)

7 Deposition of Gershom Hicks, April 14, 1764, in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21650, part 1, p. 102. Five days later, under pressure from Fort Pitt officials, Hicks recanted much of his testimony and de-emphasized the Indians' martial intentions. He apparently made no reference to smallpox in his second deposition. William Grant, Re-Examination of Gershom Hicks, in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21651, pp. 7-10. For more on Hicks, see Edward Ward to Sir William Johnson, May 2, 1764, in The Papers of Sir William Johnson, ed. Milton W. Hamilton (14 vols., Albany, 1921-1965), XI, 169-71. On the Virginia Indians, see Andrew Lewis to Bouquet, Sept. 10, 1764, in Papers of Col. Henry Bouquet, ed. Stevens and Kent, ser. 21650, part 2, p. 127. For Killibuck's account, see William Johnson, Journal of Indian Affairs, [Johnson Hall, March 1-3, 1765], in Papers of Sir William Johnson, ed. Hamilton, XI, 618. On the possibility of multiple sources of infection, see McConnell, Country Between, 195-96. M'Cullough's report is in Archibald Loudon, ed., A Selection, of Some of the Most Interesting Narratives, of Outrages, Committed by the Indians, in Their Wars, with the White People (1808; 2 vols., New York, 1977), I, 331. Knollenberg has emphasized Gershom Hicks's testimony that smallpox had ravaged the Indians "since last spring." He believes this means the disease was present among nearby tribes even before Fort Pitt personnel distributed the infected blankets on June 24. While it is possible that Knollenberg is right, he may also be investing too much precision into what Hicks intended as a general statement. Hicks had only been captured in May, and June might well be considered "spring" in the hills of western Pennsylvania. Knollenberg, "General Amherst and Germ Warfare," 494.

8 Such a communication might have been either written or oral in form. It is also possible that documents relating to such a plan were deliberately destroyed.