Island (pop., 2000: 876,165) of Hawaii, U.S. Situated between the islands of Kauai and Molokai, it occupies 607 sq mi (1,574 sq km) and is the third largest and most densely populated of the Hawaiian Islands. Of volcanic origin, it has two parallel mountain groups, the Koolau Range and Waianae Ranges, which are connected by a central plateau. It is the site of Honolulu, Pearl Harbor, and Waikiki. Military installations, tourism, pineapples, and sugar are important to its economy.
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The 2000 census showed a population of 876,151, which was essentially the entire population of Honolulu County except for 5 individuals who lived in the far-flung Northwestern Hawaiian Islands portion of the county in the United States Census Bureau's Census Tract 114.98 of Honolulu County, Hawaii.
The island is home to about 900,000 people (approximately 75% of the resident population of the state) and partly because of this, Oahu has for a long time been nicknamed "The Gathering Place". However, the term Oahu has no confirmed meaning in Hawaiian, other than that of the place itself. Ancient Hawaiian tradition attributes the name's origin in the legend of Hawaiiloa, the Polynesian navigator credited with discovery of the Hawaiian Islands. The story relates that he named the island after a son.
The city of Honolulu—largest city, state capital, and main deepwater marine port for the State of Hawaii—is located here. As a jurisdictional unit, the entire island of Oahu is in the City & County of Honolulu, although as a place name, Honolulu occupies only a portion of the southeast end of the island (essentially, the Honolulu District). The island extends from Kaena on the west end to Makapuu on the east. Well-known features found on Oahu include Waikīkī, Pearl Harbor, Diamond Head, Hanauma Bay, Kāneohe Bay, and the North Shore.
The old Kingdom of Oahu was once ruled by the most ancient Alii in all of the Hawaiian Islands. The first great king of Oahu was Mailikukahi, the law maker, who was followed by many generation of excellent monarchs. Kualii was the first of the warlike kings and so were his sons. In 1773, the throne fell upon Kahahana, the son of Elani of Ewa. In 1783 Kahekili II King of Maui conquered Oahu and deposed the reigning family and then made his son Kalanikupule king of Oahu. Kamehameha the Great would conquer Kalanikupule's force in the Battle of Nuuanu. And with the conquest of Oahu in 1795 Kamehameha founded the Hawaiian Kingdom Hawaii would not be unifed until the islands of Kauai and Niihau surrender under King Kaumualii in 1810. Kamehameha III moved his capital from Lāhainā, Maui to Honolulu, Oahu in 1845. Iolani Palace, built later by other members of the royal family, is still standing, and is the only royal palace on American soil.
Oahu was apparently the first of the Hawaiian Islands sighted by the crew of HMS Resolution on 18 January 1778 during Capt. James Cook's third Pacific expedition. Escorted by HMS Discovery, the expedition was surprised to find high islands this far north in the central Pacific. Oahu was not actually visited by Europeans until 28 February 1779 when Captain Clerke aboard HMS Resolution stepped ashore at Waimea Bay. Clerke had taken command of the ship after Capt. Cook was killed at Kealakekua Bay (Island of Hawaii) on February 14, and was leaving the islands for the North Pacific.
The opening battle of World War II in the Pacific for the United States was the Imperial Japanese Navy preemptive attack on Pearl Harbor, Oahu on the morning of December 7, 1941. The surprise attack was aimed at the Pacific Fleet of the United States Navy and its defending Army Air Corps and Marine Air Forces. The attack damaged or destroyed twelve American warships, destroyed 188 aircraft, and resulted in the deaths of 2,403 American servicemen and 68 civilians.
Today, Oahu has become a tourism and shopping haven as over five million visitors (mainly from the American mainland and Japan) flock there every year to enjoy the quintessential island holiday experience that the Hawaiian Islands and their multicultural people now personify.