Oklahoma’s historical society didn’t hold the mantle for long, as they resold the area to the Chickasaw Nation in 2017. History has it that fort Washita was built in 1842 and was used as a military post to wade off people who were a threat to the Chickasaw and Choctaw nations.Īlong the line, the Oklahoma historical society bought Fort Washita and turned it into a magnificent museum in 1962. Visiting Fort Washita’s historic site is an exciting experience.