Saint Helena (/ˌseɪnt həˈliːnə/ SAYNT-hə-LEE-nə) is a volcanic tropical island in the South Atlantic Ocean, 4,000 kilometres (2,500 mi) east of Rio de Janeiro and 1,950 kilometres (1,210 mi) west of the Cunene River, which marks the border between Namibia and Angola in southwestern Africa. It is part of the British Overseas Territory of Saint Helena, Ascension and Tristan da Cunha. Saint Helena measures about 16 by 8 kilometres (10 by 5 mi) and has a population of 4,255 (2008 census). It was named after Saint Helena of Constantinople. 

The island was uninhabited when discovered by the Portuguese in 1502. One of the most remote islands in the world, it was for centuries an important stopover for ships sailing to Europe from Asia and South Africa. Napoleon was imprisoned there in exile by the British, as were Dinuzulu kaCetshwayo (for leading a Zulu army against British rule) and more than 5,000 Boers taken prisoner during the Second Boer War.
How many Boers were taken prisoner?
more than 5,000 Boers