Lonesome Dove, Volume 2: Comanche Moon by Larry McMurtry

THE SECOND TIME the young Comanches caught him, Famous Shoes thought it was probably going to be his time to die. He had found his grandmother at a poor little camp near the Arkansas but did not have a very good visit. His grandmother had immediately set in complaining about his grandfather and had kept up her complaining for two days. Every time Famous Shoes tried to get her to consider more important things, such as how the Kickapoo people had come to be, his grandmother grew irritated and brushed aside his question. Everybody knew of course that the Kickapoo people had come out of a hole in the earth at the time when there were only buffalo in the world. The Kickapoo had been chosen by the buffalo to be the first human beings; Father Buffalo himself had pawed open the hole and allowed the Kickapoo to come up from their deep caves. Everybody knew about the hole and Father Buffalo and that the Kickapoo had become human beings at a time before rain clouds, when all creatures received their moisture from the dew; they knew that rain had only begun to fall out of the sky once the Kickapoo people had made a prayer that caused the sky to let down its waters.

But what no one knew, or, at least, what his grandmother could not be bothered to tell him, was where the hole was that the Kickapoo had come out of.