Hugo Black

“ The Navajo Reservation was set apart as a 'permanent home' for the Navajos in a treaty made with the 'Navajo nation or tribe of Indians' on June 1, 1868. [2] Long before that, in fact from the very first days of our Government, the Federal Government had been permitting the Indians largely to govern themselves, free from state interference, [3] and had exercised through statutes and treaties [4] a sweeping and dominant control over persons who wished to trade with Indians and Indian tribes. ”

“ Moreover, we hold that Indian traders trading on a reservation with reservation Indians are immune from a state tax like Arizona's, not simply because those activities take place on a reservation, but rather because Congress in the exercise of its power granted in Art. ”