Before the flu pandemic of 1918 and the Coronavirus of 2020, there was the smallpox outbreak of 1775-1777. John Adams wrote to his wife on June 26, 1776, "The smallpox is ten times more terrible than Britons, Canadians, and Indians together. The small Pox! The small Pox! What shall We do with it?" This book explores the various diseases that affected the American and British armies during the American Revolution. Much of the information has been gathered from diaries, letters, orders, newspapers, pension applications, and memoirs of the participants. It examines how diseases helped decide the outcome of some battles and may have altered the course of the war. The book also examines some possible early uses of biological warfare. Sir Jeffery Amherst, the British commander-in-chief in North America, asked "Could it not be contrived to send the smallpox among those disaffected tribes of Indians?"This complicated history of infectious diseases during the American Revolution sheds a modern light on historical illness, preventative measures, and war.