Island of Oahu (Hawaiian: O'ahu), Honolulu County, Hawaii. The Kauai and Kaiwi canals separate it from Kauai to the northwest and Molokai to the southeast.
Oahu, the most populous of the Hawaiian Islands, is the third largest in size at 597 square miles (1,546 square km) and was formed by a volcano.
The Koolau and Waianae mountain ranges run parallel to one another and are joined by a central plateau.
Around 500 CE, Tahitian settlers first set up shop on the island of Oahu. Kamehameha I, king of Hawaii, united the Hawaiian Islands by conquering Oahu in 1795.
Since 1845, when the state capital was relocated from Lahaina on Maui to Honolulu on Oahu, the city has served as both the capital of the state and the seat of its government.
During the latter half of the nineteenth century, foreign powers had begun to exert greater influence over the monarchy.