Siege of Fort Pitt Siege of Fort Pitt The Siege of Fort Pitt took place during June and July 1763 in what is now the city of Pittsburgh, Pennsylvania, United States. The siege was a part of Pontiac's War, an effort by Native Americans to remove the British from the Ohio Country and Allegheny Plateau after they refused to honor their promises and treaties to leave voluntarily after the defeat of the French. The Native American efforts of diplomacy, and by siege, to remove the British from Fort Pitt ultimately failed. This event is best known as an early instance of biological warfare, where
Fort Defiance (Ohio) had agreed not to settle. Until the War of 1812, Fort Defiance was one of the westernmost outposts in Ohio. William Henry Harrison used it as one base for his attacks against Native Americans during Tecumseh's War, and the fort played a role in the War of 1812 as well. The city of Defiance, Ohio, was founded at the fort's location. In 1904, the site of the fort was chosen for the Defiance Public Library. Fort Defiance served as a reference point for defining the boundary line of land cession in the Treaty of Detroit in 1807. This north-south line