- a solitary island in the South Atlantic, a British overseas territory; population 7,600 (est. 2009); official language, English; capital, Jamestown. It was administered by the East India Company from 1659 until 1834, when it became a British colony. Ascension, Tristan da Cunha, and Gough Island are dependencies of St Helena. It is famous as the place of Napoleon’s exile (1815–21) and death.
so named when it was first encountered by the Portuguese on the feast day of St Helena, 21 May, 1502