They had been taken.

The Century Of Legal Pursuit That Followed

The taking of the Black Hills was understood immediately by the Sioux people as an injustice, and the legal pursuit of redress began remarkably soon and continued, with extraordinary persistence, for more than a century.

The obstacles were severe.

The legal mechanisms available to Native nations seeking redress from the United States government were, for most of American history, extremely limited.

The doctrine of sovereign immunity generally prevented suits against the government without congressional consent.