Operational Group

Operational Group (Polish: Grupa Operacyjna, abbreviated GO) was the highest level of tactical division of the Polish Army before and during World War II and the Invasion of Poland. It was corps-sized, although various Operational Groups varied in size. Operational groups first appeared in Polish tactical scheme during the Polish-Bolshevik War, most probably under the influence of French Military Mission to Poland. After the war they were dissolved.

Prior to World War II, the operational groups were recreated. Initially, in March 1939, they consisted only of staffs formed around existing corps commands. According to the Polish mobilization scheme, they were to become mobile reserves of the Polish armies and other major strategic-scale units. One of such groups, the Kutno Operational Group, was planned but never created. Also, in the autumn of 1938, the Independent Operational Group Silesia was created with the purpose of capturing Zaolzie from Czechoslovakia.

Some groups were formed during the final mobilization of late August 1939, others were formed during the war as strategic considerations necessitated. Most were attached to armies, several however were independent.

In addition, during the Invasion of Poland in 1939, several other corps-sized units were formed or improvised. All of them were named after their commanding officers:

There were also several operational groups created by the Polish People's Army (Ludowe Wojsko Polskie) after the war in the years 1946-1947.

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