The youngest son of Rangi and Papa. He was a brother of Tāne, Rongo, Tū, etc., or of Tāwhiri-mā-tea. He remains at his mother's breast or, as another version has it, is still unborn. Papa was allowed retain this child in her solitude. His brothers resolved to grant him some comfort in his dark realm, hence they gave him the boon of fire, obtained from Rakahore.
Rū represents subterranean fire, and is responsible for all volcanic outbursts and earthquakes. He is furthermore associated with the change of seasons. When a shock is felt in spring time it is caused by Ruaumoko turning over; he is turning the cold down and the warmth uppermost. In the autumn he reverses the process.
His full name is Rū-wai-moko-roa, or Rū-ai-moko-roa, or Rū-au-moko.
- Best, Elsdon. (1924). The Maori. Wellington: Harry H. Tombs, pp. 106, 108, 176, 237, 409.
- Tregear, Edward. (1891). Maori-Polynesian Comparative Dictionary. Wellington: Government Printer, pp. 429-430.
- White, John. (1887). Ancient History of the Maori. 6 vols. Wellington: G. Didsbury, Government Printer, pp. 1:21, 2:4.