Teuruarii IV, born Epatiana a Teuruarii, was the last King of Rurutu, an island within the larger Austral Islands archipelago, who ruled from around 1886 until the annexation of the island to France in 1900. Proclaimed king upon his father's abdication while still a child, his mother ruled as regent. During this regency the Church of Moerari was consecrated and the death penalty was abolished.
Teuruarii's reign was disrupted by ongoing French expansionism in the Pacific. Teuruarii entreated the British to place Rurutu under a British protectorate, which the islanders deemed more favorable due to their predominant adherence to Protestantism. These efforts failed and Rurutu was proclaimed a protectorate of the French Third Republic on 27 March 1889. Teuruarii was allowed to continue ruling as king until the annexation of the island to the territory of French Oceania in 1900, today part of the overseas country of French Polynesia. Living out the remainder of his life as a village chief, Teuruarii left many descendants who would have a strong influence in the islands to the modern day.