The ancient Egyptian god known for his role in the afterlife is Osiris. He is a central figure in Egyptian mythology, representing death, resurrection, and the cycle of life. Osiris presides over the judgment of souls, determining their fate in the afterlife. His myth involves being killed by his brother Seth and subsequently resurrected by his wife Isis. This narrative reflects themes of renewal, the importance of the afterlife, and the cyclical nature of existence in Egyptian belief systems.