One hundred fifty-six years before Custer, Europeans were massacred on the high plains. Hiding in the tall grass, the Pawnee, armed by the French, surprised a Spanish/Pueblo encampment at dawn. They killed 35 Spaniards, which was most of them, including their captain Pedro de Villasur. They also killed 11 Pueblo allies, though most of the Pueblo escaped. The victory secured the northern Plains for French traders and sent the Spanish reeling back to Santa Fe.
Because of the Pawnee, and at other times the Apache and Comanche, the Spanish Empire never advanced on to the Great Plains.