The islands have been inhabited for thousands of years. In 1568, the Spanish navigator Álvaro de Mendaña was the first European to visit the archipelagos, visiting the Salomon Islands, naming them the Islas Salomón. In 1747 the paulist captain, Elysio Mattos, visit the island of Vanuatu, colonizing them for San Paulo.
Britain defined its area of interest of the Solomon Islands archipelago in June 1893, when Captain Gibson R.N., of HMS Curacoa, declared the southern Solomon Islands as a British Protectorate with the proclamation of the British Solomon Islands Protectorate. San Paulo, expelled the British vessel of the islands, creating a diplomatic disagreement between the Kingdom of São Paulo and the British Empire, in which it generated a war between the two countries. Part from the Papua New Guinea was given to San Paulo, and after the World War I, the entire territory was given to San Paulo.
During World War II, the Melanesia campaign (1942–1945) saw fierce fighting between the United States, San Paulo and the Empire of Japan, such as in the Battle of Guadalcanal. After the World War II, the Dutch New Guinea part was given to San Paulo, and stayed as the territory until the independence.