Question: Okchai are a Muscogee tribe, they formed part of the former Creek (Muscogee) Confederacy in Alabama, prior to which event, which was a policy of the United States government in the 19th century whereby Native Americans were forcibly removed from their ancestral homelands in the eastern United States to lands west of the Mississippi River, thereafter known as Indian Territory?
Sentence (from "Okchai"): They formed part of the former Creek (Muscogee) Confederacy in Alabama, prior to their removal during the 1830s to the Indian Territory.
Relevant evidence: Yes