Complex sentence: As his mother was Creek, he was raised within the Creek nation, which was matrilineal, and his mother's status gave him power within the tribe, where he became a chief, or "miko".
Split into simpler sentences: As his mother was Creek, he was raised within the Creek nation, which was matrilineal. His mother's status gave him hereditary power within the tribe, where he became a chief, or "miko".