The Gilbert and Ellice Islands (GEIC as a colony) in the Pacific Ocean were part of the British Empire from 1892 to 1976. They were a protectorate from 1892 to 12 January 1916, and then a colony until 1 January 1976. The history of the colony was mainly characterized by phosphate mining on Ocean Island. In October 1975, these islands were divided by force of law into two separate colonies, and they became independent nations shortly thereafter: the Ellice Islands became Tuvalu in 1978, and the Gilbert Islands became part of Kiribati in 1979.
The Gilbert Islands (sometimes also known as Kingsmill Islands or King's-Mill Islands) are a chain of sixteen atolls and coral islands in the western Pacific Ocean. They are part of Remote Oceania, and traditionally part of the Micronesia subregion of Oceania. The Gilbert Islands are the main part of what is now the Republic of Kiribati ("Kiribati" is the Gilbertese rendition of "Gilberts") The atolls of the Gilbert Islands are arranged in an approximate north-to-south line.
Geographically, the Equator is the dividing line between the northern Gilbert Islands and the southern Gilbert Islands. South of the Gilbert Islands lie the Ellice Islands (now called Tuvalu), which were previously politically connected with them. The Ellice Islands comprise three reef islands and six true atolls, spread out between the latitude of 5° to 10° south and longitude of 176° to 180°, west of the International Date Line. The Ellice Islands are midway between Hawaii and Australia, and they, too, lie in the Polynesia subregion of Oceania.
In 1568, when Spanish navigator Álvaro de Mendaña de Neira was commissioned to explore the South Pacific, he sailed relatively close to the Gilbert Islands. He sailed between the Line Islands and the Phoenix Islands, but without sighting land. However, he ultimately discovered what he called "Isla de Jesús", (probably Nui, amongst the Ellice island group).
In 1606, Pedro Fernandes de Queirós sighted two of the islands in the Gilbert island group: Butaritari and Makin, which he named the Buen Viaje Islands (‘good trip’ islands in Spanish).