As a result of this final concession, the Five Tribes lost the western half of present Oklahoma. These treaties had a tremendous impact on future relations between the federal government and the Five Tribes. The influx of whites moving into I.T. after the Civil War pressed for statehood during the 1890s and early 1900s. However, tribe members fought to retain their sovereignty based on the clause in the Reconstruction Treaties that stated that no federal legislation could interfere with or annul their tribal organization.