The first settlers of Hawaii were Polynesians, who probably arrived around 2,000 years ago. They were displaced by another wave of Polynesians from Tahiti around 1200. Although some European travelers may have stopped on the islands as early as the 1500s, the islands were not revealed to the world until Captain James Cook of the British navy landed in 1778 and named the islands the Sandwich Islands in honor of the Earl of Sandwich. Cook was killed in a dispute with the Hawaiians the following year. Although the population may has been as high as 300,000 as the time of first contact with Europeans, imported diseases killed many of the natives by the early 1800s. A local chief named Kamehameha began a bloody campaign to control the islands in 1782 and after 10 years defeated his enemies with the help of arms supplied by whites. In 1795, he became king of the Kingdom of Hawaii, which controlled most of the islands. The remainder acknowledged him in 1810. He was succeeded by his son Kamehameha II in 1819. The first constitution was adopted in 1840. Hawaii's independence was recognized by the United States in 1842. Sugar and pineapple plantations became mainstays of the economy. In 1891, King Kalakaua died and was succeeded by his sister Liliuokalani. Queen Liliuokalani tried to increase her power and was overthrown by a bloodless coup in 1893 led by Americans and other foreigners. The Republic of Hawaii was established, but American business interests wanted the islands to become part of the United States. Hawaii was annexed in 1898 and territorial government was established in 1900. On December 7, 1941, Japanese aircraft attacked United States military targets on Hawaii, primarily Pearl Harbor, with large losses of ships and lives. The bases were repaired and became the headquarters for the war against Japan in the Pacific. In Congress, a generally racist view of the non-white population of Hawaii prevented the islands from becoming a state until 1959, when it was admitted following a referendum that overwhelming approved statehood. Since statehood, the economy has become more dependent on tourism, both from the United States and Japan.