Song of the Earth by John R. Dann
After a volcano erupted and destroyed their tribal home, and powerful daughters of River Woman saved young Grae from a flooded river and made him chief, but that's almost the last thing they agree on before the tribe splinters. Grae leads the main group out of Africa and into central and eastern Europe, searching for safety and a better life. Challenged by truly monstrous evil tribes and guided by spirits, they survive. It takes three generations, and three chieftains named Grae, before the tribe comes to rest. Their story is an adventure on the grandest scale, full of thrilling dangers, romance, and beguiling mystery in an exotic setting. A rich and complex story told with simplicity, authenticity, and vigour.