The British Army attempted use of smallpox against Native Americans during the Siege of Fort Pitt in June 1763. A reported outbreak that began the spring before left as many as one hundred Native Americans dead in Ohio Country from 1763 to 1764. It is not clear, however, whether the smallpox was a result of the Fort Pitt incident or the virus was already present among the Delaware people as outbreaks happened on their own every dozen or so years and the delegates were met again later and seemingly had not contracted smallpox. During the American Revolutionary War General George Washington believed that it was no coincidence that there was a major smallpox epidemic that coincided exactly with the beginning of the war. In the battles of Boston and Quebec British soldiers infamously and intentionally sent out smallpox-infected civilians and prostitutes to the American lines to infect and kill them with smallpox and this almost destroyed Washington's army. Washington inoculated his soldiers as a result and this saved his army against this crude method of biological warfare. It is likely that the British Marines used smallpox in New South Wales, Australia, in 1789. Dr Seth Carus (2015) states: "Ultimately, we have a strong circumstantial case supporting the theory that someone deliberately introduced smallpox in the Aboriginal population."