What caused the end of the British-American Indian alliance in the War of 1812?

The British-American Indian alliance depended heavily on Shawnee leader Tecumseh, who helped unite Native nations and coordinate their support for the British. Tecumseh was killed at the Battle of the Thames in 1813, weakening the alliance and ending much of the organized Native resistance alongside Britain. The correct choice is D, the death of Tecumseh in the Battle of the Thames.

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