This granted tribes unsettled western prairie land in exchange for their territories within state borders

Answer:Indian removal act

Explanation:

The Indian removal act was signed into law by the former president of the United States of America known as President Andrew Jackson on the 28th of May, 1830 it involved a negotiated arrangements between the Government and the native Americans who recide in the Southern parts of the United States of America to relocate to a federal territory west of the Mississippi River in exchange for white settlements.