A foreign fighter is someone who travels abroad to participate in an armed conflict, or fights for a country of which he or she is not a national. However, different definitions have been used by different journalists, policymakers, and researchers, depending on what distinctions they've wished to make.

See also French Foreign Legion Spanish Foreign Legion Portuguese Foreign Legion International response to the Spanish Civil War International Brigades Foreign support of Finland in the Winter War Mahal (Israel) Waffen-SS foreign volunteers and conscripts Foreign volunteers in the Rhodesian Security Forces Foreign fighters in the Croatian War of Independence Foreign fighters in the Bosnian War Foreign fighters in the Syrian Civil War and War in Iraq Foreign fighters in the Russo-Ukrainian War Ukrainian volunteer battalions Controversy surrounding Swedish jihadist foreign fighters Final Report of the Task Force on Combating Terrorist and Foreign Fighter Travel List of foreign volunteers

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