Fort Pitt Museum Pitt, after William Pitt the Elder. As a result, in 1763 local Delawares and Shawnees took part in Pontiac's Rebellion, an effort to drive the British out of their territory. The Indians' siege of Fort Pitt began on June 22, 1763, but the fort was too strong to be taken by force. In negotiations during the siege, the commander of Fort Pitt gave two Delaware emissaries blankets that had been exposed to smallpox, in hopes of infecting the surrounding Indians and ending the siege. The effectiveness of this attempt is unclear. Outbreaks of smallpox had plagued Native Americans for years
Illinois campaign the region. When the American Revolutionary War began, in 1775, the Ohio River marked the border between the Illinois Country and Kentucky, an area recently settled by American colonists. The British had originally sought to keep American Indians out of the war, but in 1777 Lieutenant Governor Hamilton received instructions to recruit and arm Indian war parties to raid the Kentucky settlements, opening a western front in the war with the rebel colonists. "From 1777 on," wrote historian Bernard Sheehan, "the line of western settlements was under almost constant assault by white-led [Indian] raiding parties that had originated at Detroit."