The 5-4 majority ruling applies to territory given to the Muscogee (Creek) Nation but could also be extended to land provided to other Native American tribes in the 19th century.

That would mean that only federal prosecutors can bring criminal charges against Native Americans living in a vast area covering most of the eastern section of the state, including its second-largest city, Tulsa.

Sara Hill, the Attorney General for the Cherokee Nation, who submitted a brief in support of the Muscogee (Creek) Nation, said the ruling reaffirms tribal sovereignty.

She told radio station KOSU: “There’s an emotional reaction to seeing the Supreme Court say what, you know, tribes and tribal advocates have been saying for a long time, which is that these promises that were made in these treaties had meaning.”