List of monarchs of Mangareva
The island of Mangareva, in the Gambier Islands of Polynesia, was a monarchy until its annexation by France on 21 February 1881. Although there were other monarchs of the Gambier Islands like Taravai, the kings of Mangareva were considered of the highest ranking.
Source: Wikipedia — List of monarchs of Mangareva (CC BY-SA 4.0)