In Mangaian society, the ritual system to become the principal chief, "Te Mangaia", emphasized the worship of Rongo. The installation of a new "Te Mangaia" after a war of conquest of the "puna" lands required a human sacrifice to Rongo. He was both the god of war and god of taro irrigation; his regular peacetime offerings were parcels of cooked taro. The ideological linkages between Rongo, war, taro, and human sacrifice were complex: Rongo assured success in war and fertility of the land, but these required continual sacrifices in both human bodies and taro in an endless cycle. He would feast on the souls of those who died in battle.