Looking at the ethnohistoric sources of the Crow Indians can help construct the settlement and subsistence patterns of the prehistoric counterparts of the Crow. According to one source, Joseph Medicine Crow's book From the Heart of the Crow Country, the reader is informed that when the Absarokee separated from the main tribe, believed to be the Hidatsa, they abandoned the ways of agriculture and went back to the nomadic ways of hunting and gathering. Because of the hunting they were always on the move and this lead to constant warfare with other tribes of the Plains and the mountains for prime locations (Medicine Crow 1992: 4). As far as the social organization, the primary uni