During the War of 1812, the Indiana Territory was the scene of numerous engagements which occurred as part of the conflict's western theater. Prior to the war's outbreak in 1812, settlers from the United States had been gradually colonizing the region, which led to increased tensions with local Native Americans and the outbreak of Tecumseh's War. In 1811, Tecumseh's confederacy, formed in response to encroachment by white American settlers, was defeated by U.S. forces at the Battle of Tippecanoe. After the conflict broke out, most Native Americans in the region joined forces with the British Empire and attacked American forces and settlers in concert with their British allies.
Numerous American citizens from Indiana enlisted in United States Army and militia units during the war, including the Indiana Rangers, and served in various theaters. In September 1812, months after the war's outbreak, British-allied Native Americans laid siege to two U.S. military forts in Indiana, Fort Harrison and Fort Wayne. Both sieges were unsuccessful as the besiegers were eventually forced to withdraw due to a lack of reinforcements. On November 1812, U.S. forces were defeated in Indiana by Native Americans at the Battle of Wild Cat Creek, but achieved a success next month at the Battle of the Mississinewa.
In 1813, violent skirmishes between U.S. troops and settlers and Native Americans increased, and in April the indecisive Battle of Tipton's Island occurred. William Henry Harrison, the unpopular governor of Indiana, led U.S. military efforts in the western theater. After the United States Navy defeated a smaller Royal Navy force at the Battle of Lake Erie in September 1813, British forces under the command of Henry Procter were forced to abandon Detroit and retreated into Upper Canada. American forces under Harrison's command pursued them and defeated a combined British-Indian force at the Battle of the Thames, killing Shawnee leader Tecumseh. The war resulted in the collapse of British proposals for an Indian barrier state and the solidification of U.S. control over Indiana.