Eighteenth Army or 18th Army may refer to:
Germany
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18th Army (German Empire)
The 18th Army (german: 18. Armee / Armeeoberkommando 18 / A.O.K. 18) was an army level command of the German Army in World War I. It was formed against France on 27 December 1917 from the former Heeresgruppe Woyrsch command. It served exclusi ...
, a World War I field Army
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18th Army (Wehrmacht)
The 18th Army (German: ''18. Armee'') was a World War II field army in the German ''Wehrmacht''.
Formed in November 1939 in Military Region (''Wehrkreis'') VI, the 18th Army was part of the offensive into the Netherlands (Battle of the Netherlan ...
, a World War II field army
Others
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18th Army (Soviet Union)
The 18th Army of the Soviet Union's Red Army was formed on 21 June 1941 on the basis of HQ Kharkov Military District and armies of the Kiev Special Military District.
The Army's commander in 1941 was General-Lieutenant Andrey Smirnov. The Army c ...
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Eighteenth Army (Japan)
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18th Combined Arms Army
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