In Māori mythology, Rongo is a major god, the god of cultivated food, especially the kūmara, a vital food crop. Other food crops cultivated by Māori in traditional times include taro, yams (uwhi), cordyline (tī), and gourds (hue). Because of their tropical origin, most of these crops were difficult to grow except in the far north of New Zealand. Hence the importance of Rongo.
Rongo, with his brothers Tū, Tāne, Tāwhirimātea, Tangaroa and Haumia-tiketike, separated the primordial parents Rangi and Papa to allow daylight into the world. Tāwhirimātea, the god of storms, did not consent to this plan and afterwards attacked his brothers with unrelenting fury. Rongo and Haumia, the god of wild food, took refuge in the body of Papa, mother earth, who hid them until the storm passed (Grey 1956:7, Tregear 1891:424,Orbell 1998:121).
In the Māori language, ‘rongo’ means peace. Rongo is generally portrayed as the creator of the kūmara, a plant associated with peace (probably because the intense cultivation it needed was best performed in times of peace). In Ngāti Awa traditions, Rongo is a son of Tāne and father of the kūmara, but a man named Rongo-māui travels to the star Whānui, obtains the kūmara and returns to Earth with it.
Small statues representing Rongo were once placed alongside kumara fields.
In Cook Islands mythology, Rongo was the god of agriculture and one of the children of Vatea (sky father) and Papa (earth mother). His twin brother was Tangaroa, the god of the sea. Rongo was the principal deity of Mangaia.
In the Mangaian legend of origin, the three sons of Rongo lifted the island up from the deep, becoming the first settlers and the ancestors of the Nga Ariki tribe. The traditional name of the island was A'u A'u, which literally means 'terraced', short for A'u A'u Nui o Rongo ki te Ao Marama (Great Terraced Land of Rongo in the Land of Daylight).