How did meeting the Crows change the Kiowas?

Momaday mentions briefly the relationship between the Kiowas and the Crows in his Introduction. He offers not only a quick lesson in Native American history, but also one of U.S. geography. The Kiowas originated in the area of the Yellowstone River, in western Montana and northern Wyoming, close to the Rocky Mountains. At the end of the 1600s, they began to migrate away from the mountains: first to the east, to the smaller Black Hills of western North Dakota. Here they met and became friendly with the Crows, “who gave them the culture and religion of the Plains,” according to the author. Once you leave the Black Hills, this central part of the continent becomes the Plains, with long stretches of open grassland and few hills.  The Crows were familiar with this land, and they could show the others how to best live on it. The Kiowa-Crow friendship fostered a focus on the importance of the sun and the Sun Dance, as well as on the use of horses for transportation and battle. Later the Kiowas moved south and settled in southwestern Oklahoma in the 1800s, away from the mountains and the hills; and moving always toward the sun.