Tagaroa was the most prominent of the Rotuman high gods, identified specifically as the god of human fertility and as the deity of the sau (sacred king) and the mua, the two title-holders who presided over the island's ritual cycle. The high gods, of whom Tagaroa was foremost, were regarded as the source of sustenance and were prayed to for rain, for fruitful land and for success in undertakings affecting the whole island. He bears the same name as the great Polynesian god Tangaroa (Samoan Tagaloa), and on Rotuma stands at the centre of the fertility religion alongside the supreme 'God Above', Tagroa Siria.