The American Indian Wars is a catch-all title for the conflicts between settlers to America and the indigenous people already there. Over several centuries, as broad as that sounds, the impact was the takeover of the American continent by the colonialists, and the social, political and cultural… and of course territorial defeat of Native Americans.
Buffalo Soldiers were the U.S. cavalrymen around the time, who were black. Perhaps many were freed slaves, now enslaving others? Marley wanted people to reflect on their origins and not to repeat mistakes committed against them: “If you know your history, then you would know where you coming from.”
Is Marley criticizing African Americans for hypocrisy?
Maybe not: that the buffalo soldiers, taken from Africa, were still fighting for their own survival in America. In fact, they enlisted voluntarily, but with few economic opportunities, options were limited. Buffalo soldiers are thus yet another example of black oppression. This continued, Marley believed at the time of writing (1980), with dreadlocked rastafarians.