Kai-n-Tiku-Aba

In Polynesian mythology (specifically: Kiribati), Kai-n-Tiku-Aba ("tree of many branches") is a sacred tree located in Samoa, which grew on the back of a man named Na Abitu. Koura-Abi, a destructive man, broke it. Sorrowful, the people of Samoa scattered across the world.

This myth is known from Kiribati, and explains why they migrated there from Samoa.