Muhacir (sometimes maacir in colloquial Turkish) is a term of Arabic origin (مهاجر, Muhajir or Mohajir) in Turkish language, used across ethnicities, and that corresponds to people whose ancestors migrated from formerly Muslim territories (Dar al-Islam in Islamic terminology), considered lost to the non-Muslims (Dar al-harb): the Balkans (Turks, Pomaks, Albanians, Bosniaks), Caucasus (Abkhazians, Ajarians, 'Circassians', Lazs, Chveneburis, Chechens), Crimea (Tatars), Crete (Cretan Turks) or Africa (Sudanese Mahdists, Algerian partisans of Emir Abdelkader, Senussi insurgents from Libya).
After the end of Ottoman rule (especially after 1878 and 1912), a large portion of the Muslim populations of these geographies took refuge in Turkey.