Archaeologists believe that humans arrived on Papua New Guinea some 50,000 years ago, presumably by sea from Southeast Asia. A Spanish navigator, Don Jorge de Meneses, is credited with naming it "Papua" a Malay word for the frizziness of Melanesian hair. The term "New Guinea" was applied to the island in 1545 by a Spaniard, Ynigo Ortis de Retez, because of a similarity between the islands' indigenous people and those found on the African Guinea coast.
European traders, adventurers and gold explorers visited in the 16th and 17th centuries, but land claims did not begin until 1828, when the Dutch took control of the western half of New Guinea, now Papua Province of Republic of Indonesia. Due to the rugged terrain and isolated village communities, the impact of colonization varied throughout the nation.
Prior to World War II, Papua New Guinea was two separate territories. The territory of Papua was a British colony until 1884, and was later ceded to Australia to administer. New Guinea was part of the pre-World War I German Empire, but it too was given to Australia to administer at the end of World War I. During World War II, Japanese forces occupied PNG. Following the war, and the expulsion of Japanese forces, the two territories were amalgamated into one, which became known as the Territory of Papua and New Guinea.
Australia focused its efforts on developing PNG's cash economy and the democratization of the central government. The Papua and New Guinea Act of 1949 provided for a Legislative Council, judicial system, a civil service and a local government system. A generally protectionist policy pervaded and characterized Australia's efforts in the 1950s. In 1964, the first House of Assembly was established to provide Papua New Guineans a greater role in the country's political decision-making process. With domestic and international pressure for independence mounting, preparations for political independence began in earnest in the late 1960s and into the 1970s.
In 1972, Michael Somare became Chief Minister of a democratically elected government, and in 1973 the country was administratively unified and renamed Papua New Guinea. Papua New Guinea became fully independent nation on September 16, 1975.