a republic in NE Africa, on the Red Sea: conquered by Mehemet Ali of Egypt (1820–22) and made an Anglo-Egyptian condominium in 1899 after joint forces defeated the Mahdist revolt; became a republic in 1956; a lengthy civil war between separatists in the mainly Christian south and the government resulted in independence for South Sudan following a referendum in 2011. It consists mainly of a plateau, with the Nubian Desert in the north. Official languages: Arabic and English. Official religion: Muslim; there are Christian and animist minorities. Currency: Sudanese pound or Sudani (replaced the Sudanese dinar in 2007). Capital: Khartoum. Pop: 40 533 330 (2017 est). Area: 1 861 484 sq km (718 723 sq miles)