Until 1870 Native Americans participated in many wars, both for and against Europians or later, the American governmet. Sometimes an alliance with them determined a key factor to win among imperial rivalries. Intertribal antagonisms were often used for one force to use their hostility and suspicion against the opponent, which, in several cases was even another tribe. Nationalistics rivalries were easy to use, because these existed even long before the arrival of the Europeans. Native tribes were belligerents among them from before.
Expansionist wishes of non-Indians exacerbated tensions between them too.
Indians were usually employ as auxiliares infusing new life and ferocity to the war efforts of one part against the other.
In some periods, large Indian confederations tipped the balance of negotiations from one side to another. Indian raids ecouraged from one side were influential in causing damages with skirmish tactics against the other side.
After 1830, guerrilla-style actions took place each time that Indians refused to be relocated.
