Saint Helena, Ascension and Tristan da Cunha[3] is a British Overseas Territory located in the South Atlantic and consisting of the island of Saint Helena, Ascension Island and the archipelago of Tristan da Cunha including Gough Island. Its name was Saint Helena and Dependencies until 1 September 2009, when a new constitution came into force giving the three islands equal status as three territories, with a grouping under the Crown.

History

Of volcanic origin, the islands of Saint Helena, Ascension Island, and Tristan da Cunha were all formerly separate colonies of the English crown, though separately discovered by several Portuguese explorers between 1502 and 1504.

Reference: Wikipedia