During the American Revolution, our brave soldiers faced more than just redcoat bullets. An invisible enemy, smallpox, tore through their encampments, claiming lives ten times faster than any battlefield wound. While British troops often carried immunity, many Continental Army soldiers had never encountered the disease, leaving them vulnerable to fever and infection. This silent killer ravaged entire units, posing a threat so profound it shaped the very course of the fight for freedom.
Imagine a battle where the most dangerous weapon wasn’t a musket, but a cough. Smallpox didn’t just sicken individuals; it crippled armies, even thwarting critical campaigns like the one to capture Canada. Yet, amidst this widespread terror, General George Washington himself carried a unique immunity, allowing him to navigate the infected camps without fear. Join us now as we uncover the gripping, untold story of how this devastating disease, far from the battlefield, became a surprising — and nearly insurmountable — challenge in the birth of our nation.
📖 Read the Episode Transcript
Take it away! Smallpox is ten times more terrible. The quote from John Adams is, “Disease has destroyed ten men for us, where the sword of the enemy has killed one.” This was in a letter John Adams wrote to his wife, Abigail, April thirteenth, seventeen seventy-seven. During the Revolution, soldiers were plagued with typhoid, yellow fever, and smallpox, which and estimated thirty percent of the soldiers became infected with. So the soldiers were living in tight quarters, and so the diseases could spread easily, and they didn’t always have proper sanitation. So this largely began when the British evacuated Boston. The British had occupied Boston for nine months, and when they finally left Boston, they left their infected soldiers behind. So, spreading across the continent, smallpox epidemic killed an estimated one hundred and forty-five thousand settlers and Indians. Fortunately for General George Washington, he was immune to smallpox, and by this time, he’s nineteen. He accompanied his older half-brother, Lawrence Washington, to the island of Barbados, and he gets smallpox. The year is seventeen fifty-one. Washington recovered, and he came back to America. His older brother died, and George inherited Lawrence’s estate, and the rest is history. But now he’s immune to smallpox, and so when the army gets the disease, he can go amongst the army and not be affected. On July fourth, seventeen seventy-five, Washington cautioned against trap around Boston. He said, “As there may be danger of introducing smallpox into the army.” Now, they didn’t know about diseases. It wasn’t until the middle eighteen hundreds that you had Louis Pasteur in the microscope and discovering viruses and so forth. So they weren’t sure how this spread. Even John Adams, when he would write letters to his wife, Abigail, she would insist that he smoke the letters. “What’s that?” Well, they would write the letter and put it in a box and light a little fire underneath of it, and they felt maybe the smoke will kill the virus. On December fifteenth, seventeen seventy-five, George Washington explained to Joseph Reed, “Smallpox is in every part of Boston, a surety against any attempt of ours to attack.” If we escape the smallpox in this camp, it will be miraculous. Every precaution that can be taken to guard against this evil. On December fourth, seventeen seventy-five, Washington informed Congress that the British were sending civilians infected with smallpox out of the city. So Washington said, “By recent information, General Howe is going to send out a number of inhabitants. A sailor says that a number of these coming out have been inoculated with the design of spreading smallpox through the camp.” So the British, back when they did have Boston for those nine months, the word was that they were intentionally infecting people with the smallpox and intentionally sending them out to George Washington’s troops. On January first, seventeen seventy-seven, British ships sailing under a flag of truce were leased four hundred American prisoners who were suffering from smallpox. They released them at Connecticut’s Milford Harbor. So you think, “Oh, great, here’s the British, like one of those prison ships, and they’re going to let some Americans go!” Well, the ones that they let go are infected with smallpox. Within a month, forty-five had died, along with one of their caregivers, Captain Stephen Stowe. The British officer Duncan had suggested, as cited in a book published in seventeen seventy-seven, “Dip arrows in matter of smallpox and twang them at the American rebels. This would disband these stubborn, ignorant, enthusiastic savages.” Now, Quebec, Canada, may have been captured by Americans in December, seventeen seventy-five, and Canada then could have become part of the United States had it not been for smallpox. American Captain Hector McNeil told of a Congressional committee investigating the failure of the army’s expedition to Canada. He said, “Smallpox was sent out of Quebec by British Governor Guy Carleton, inoculating the poor people at government expense, for the purpose of giving it to our army.” So the situation was: General Benedict Arnold — he had been a hero up to this point before he flipped and became a trader — . But Benedict Arnold was leading an American army up to Canada, and they could have captured Montreal, they could have captured Quebec. But he reported that nearly twelve hundred American troops at Montreal, where they were camped, were suffering from smallpox. So, out of his twelve hundred men, he only had five hundred that could fight. So here you have a General Sullivan. He’s got militia. They’re supposed to go up join this army, and they’re like, “Oh, we don’t know, we want to join it. Do you have all these people sick and dying of smallpox?” General Gates conceded, “As fine an army as has ever marched into Canada has this year been entirely ruined with smallpox.” The line of retreat extended nearly thirteen miles distance, and a great part of them sick with smallpox. John Adams wrote from Philadelphia, June of seventeen seventy-six. Our misfortune in Canada are enough to melt a heart of stone. The smallpox is ten times more terrible than Britain’s, Canadians, and Indians together. This was the cause of our precipitate retreat from Quebec. They did develop a method of inoculating, where the pox would scab over and they would scrape to scab and get powder from it, and then they would blow it up somebody’s nose. The threat of smallpox did not lessen until widespread inoculations were called for by Doctor Benjamin Rush. Rush was a member of the Continental Congress, where he signed the Declaration of Independence. He is considered the father of American medicine. Doctor Rush personally inoculated Virginia Governor Patrick Henry against smallpox, as well as Pennsylvania’s troops, resulting in their low rate of illness. So he was doing a little section of the troops here, another section of the troops there, and they would get sick for a little while and recover. So Doctor Benjamin Rush began to make this important contribution against this deadly enemy of smallpox.
And a great job as always by Greg Hengler on that piece, and a special thanks to William Federer. He is a nationally known speaker, best selling author, and president of Amerisearch, Inc., a publishing company dedicated to researching America’s heritage. And so we learn why Canada isn’t a part of the United States, the story of smallpox and the Revolutionary War. Here on Our American Stories.
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