Just last night I was reading an article about that. It pertained to the Choctaws and varied in different "clans" of the choctaw people. But some did marry more than once, usually to a sister or other family member of the wife. It was at the request of the wife, usually because the sister had lost her husband or circumstances such that. This practice was stopped around mid 1800s I think, if I remember correctly. It didn't mention a limit on the number of wives. All the wives shared the same duties and privileges as the first original wife except one. Only the first wife was allowed to share the eating bowl of the husband. Divorce was varied also, but the process was simple. If you want to read this info, I'll find the URL for you. Just let me know. Shelley