Overview
The armed forces of many nations have, at one time or another, used foreign volunteers who are motivated by political, ideological or other considerations to join a foreign army. These may be formed into units of a given nationality or may be formed into mixed nationality foreign units. Sometimes foreign volunteers were or are incorporated into ordinary units. The practice has a long history, dating back at least as far as the Roman Empire, which recruited non-citizens into Auxiliary units on the promise of them receiving Roman citizenship for themselves and their descendants at the end of their service.
Mixed nationality units
Historic
60th (Royal American) Regiment of Foot. Composed of 'foreign Protestants'.
Boer foreign volunteers
Hohenlohe Regiment of France during the Bourbon Restoration.
International Brigades of the Spanish Civil War
Islamic Legion
Kenpeitai Auxiliary units consisted of regional ethnic forces that were organized in areas occupied by the Japanese.
King's African Rifles
The SS (particularly the Waffen-SS) made extensive use of foreigners during World War II. For more information, see: Waffen-SS foreign volunteers and conscripts
Rhodesian Light Infantry (initially all-Rhodesian, this unit became the "Foreign Legion" of the Rhodesian Army)
Mahal – non-Israeli volunteers who fought for Israel in the 1948 Arab–Israeli War. There is to this day a voluntary program called Mahal in the Israeli army.
Afghan mujahideen
Bosnian mujahideen were foreign Muslim volunteers who fought on the Bosniak side during the Bosnian War.
Current
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