What is today known as Sella Bay was a village known as Sidya prior to Spanish colonization.

During the Spanish CHamoru Wars in the 17^th century, Sidya sided with the Spanish against its neighbor Aty, which was located where Cetti Bay is today. Sidya was notable at the time for being one of the few villages where the Spanish explicitly acknowledged the power of a Maga’håga, or a woman who held political sway over men.

Following the end of the wars, CHamorus were forced to leave Sidya along with most other villages in Guam and settled into new villages where the Spanish could more easily watch over them. This was something carried out in all the islands of the Marianas except for Rota.  

Until the 19^th century the southern village of Humåtak was the main port of entry for ships to the island. Because of this a road was built connecting Hagåtña the capital with Humåtak along the southwestern coast of Guam. That road required the building of several bridges, one of which still stands at Sella Bay.

In the 1970s the US military began negotiations with the Government of Guam over the taking of Sella Bay in order to build an ammunition wharf. A diverse coalition of educators, political leaders and young community activists voiced their opposition to the use of this area which contained ancient artifacts of CHamoru life and was a favorite hiking destination. The protests were successful and the wharf was built in Apra Harbor instead.