21st Army may refer to:
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21st Army (Wehrmacht)
The 21st Army was a German field army in World War II.
On 27 April 1945, towards the end of the war in Europe, the 21st Army was formed from Headquarters, 4th Army as part of Army Group Vistula
Army Group Vistula () was an Army Group of the ...
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21st Army (Soviet Union)
The Soviet 21st Army was a field army of the Red Army during World War II.
Operational history
June–September 1941
21st Army was a part of the Second Operational Echelon of the Red Army. It was formed from the forces of the Volga Military Dis ...
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Twenty-First Army (Japan)
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21st Army Group
The 21st Army Group was a British headquarters formation formed during the Second World War. It controlled two field armies and other supporting units, consisting primarily of the British Second Army and the First Canadian Army. Established in ...
, Britain
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21st Group Army
The 76th Group Army (), formerly the 21st Group Army, is a military formation of the Chinese People's Liberation Army Ground Forces (PLAGF). The 76th Group Army is one of twelve total group armies of the PLAGF, the largest echelon of ground force ...
, China
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