Complex sentence: Powhatan died in 1618, after which the chiefdom was ultimately passed to his younger brother Opechancanough, who led the Indian Massacre of 1622 as well as a second attack in 1644.
Split into simpler sentences: Powhatan died in 1618, after which the chiefdom was ultimately passed to his younger brother Opechancanough. He is the one who led the Indian Massacre of 1622 as well as a second attack in 1644.