Riverworld (2003)

After an astronaut crashes, he finds himself in a rejuvenated body on a Waterworld. He also finds that he is surrounded with souls from many different eras and an alien being that died on Earth in the future. Immediately captured by a ruling group, the astronaut finds himself leading a group fighting for freedom.

Also the soul of Nero Claudius has found its way to Riverworld and wants to resume his role as Emperor.