For Serbian police Operational Group see Operational Group (Serbia).

Operational Group was the highest level of tactical division of the Polish Army before and during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 and the Invasion of Poland

Invasion of Poland (1939)

The Invasion of Poland, also known as the September Campaign or 1939 Defensive War in Poland and the Poland Campaign in Germany, was an invasion of Poland by Germany, the Soviet Union, and a small Slovak contingent that marked the start of World War II in Europe...

. It was corps

Corps

A corps is either a large formation, or an administrative grouping of troops within an armed force with a common function such as Artillery or Signals representing an arm of service...

-sized, although various Operational Groups varied in size.

They first appeared in Polish tactical scheme during the Polish-Bolshevik War, most probably under the influence of French Military Mission to Poland

French Military Mission to Poland

The French Military Mission to Poland was an effort by France to aid the nascent Second Polish Republic after it achieved its independence in November, 1918, at the end of the First World War. The aim was to provide aid during the Polish-Soviet War , and to create a strong Polish military to serve...

. After the war they were dissolved.

Prior to World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, the operational groups were recreated. Initially, in March of 1939, they consisted only of staffs formed around existing corps

Corps

A corps is either a large formation, or an administrative grouping of troops within an armed force with a common function such as Artillery or Signals representing an arm of service...

 commands. According to the Polish mobilization scheme, they were to become mobile reserves of the Polish armies and other major strategic-scale units.

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.

• Independent Operational Groups

1. Independent Operational Group „Polesie
   Independent Operational Group Polesie
   Independent Operational Group Polesie was one of the Polish Army Corps that defended Poland during the Invasion of Poland in 1939. It was created on 11 September 1939 and was commanded by general Franciszek Kleeberg...
   
   ” (Samodzielna Grupa Operacyjna Narew) under gen. Franciszek Kleeberg
   Franciszek Kleeberg
   Franciszek Kleeberg was a Polish general. He served in the Austro-Hungarian Army before joining the Polish Legions in World War I and later the Polish Army. During the German Invasion of Poland he commanded Independent Operational Group Polesie...
   
   . Created around September 9th-11th.
2. Independent Operational Group „Narew
   Independent Operational Group Narew
   Independent Operational Group Narew was one of the Polish Army Corps that defended Poland during the Invasion of Poland in 1939...
   
   ” (Samodzielna Grupa Operacyjna Polesie) under gen. Czesław Młot-Fijałkowski. Created on March 23rd
3. Operational Group „Wyszków
   Wyszków
   Wyszków is a town in northeastern Poland with 26,500 inhabitants . It is the capital of Wyszków County . Wyszków is situated in the Masovian Voivodeship ; previously it was in Warsaw Voivodeship and Ostrołęka Voivodeship .-Description:The village of Wyszków was first documented in 1203. The town...
   
   ” (Grupa Operacyjna Wyszków) under gen. Wincenty Kowalski
   Wincenty Kowalski
   Wincenty Kowalski was a Polish military commander and a general of the Polish Army. A veteran of both the World War I and World War II, he fought in all the inter-war conflicts of Poland...
   
   . Created on September 1st.
4. Operational Group „Grodno” (Grupa Operacyjna Grodno) under gen. Józef Olszyna-Wilczyński
   Józef Olszyna-Wilczynski
   Józef Konstanty Olszyna-Wilczyński was a Polish general and one of the high-ranking commanders of the Polish Army. A veteran of World War I, Polish-Ukrainian War and the Polish-Bolshevik War, he was murdered by the Soviets during the Polish Defensive War of 1939.-Early life:Józef Wilczyński was...
   
   . Created in early September; disbanded on September 10th before the battle of Grodno
   Battle of Grodno (1939)
   The Battle of Grodno took place between 21 September and 24 September 1939, during the Soviet invasion of Poland. It was fought between improvised Polish units under Gen...
   
    begun; most units moved towards Lwów.
   • Cavalry Operational Group (or Operational Group of Cavalry)
5. Cavalry Operational Group Abraham (Grupa Operacyjna Kawalerii Abraham) under Roman Abraham
   Roman Abraham
   Roman Abraham was a Polish cavalry general, commander of Wielkopolska Cavalry Brigade during German and Soviet Invasion of Poland in September 1939, in Battle of Bzura commander of Polish cavalry ....
   
   
6. Cavalry Operational Group Anders (Grupa Operacyjna Kawalerii Anders) under gen. Władysław Anders
7. Cavalry Operational Group No.1 (Grupa Operacyjna Kawalerii Nr 1)
8. Cavalry Operational Group No.2 (Grupa Operacyjna Kawalerii Nr 2)
   • Operational Groups as part of armies
9. Operational Group „Bielsko
   Bielsko
   Bielsko was until 1950 an independent town situated in Cieszyn Silesia, Poland. In 1951 it was joined with Biała Krakowska to form the new town of Bielsko-Biała. Bielsko constitutes the western part of that town....
   
   ” (Grupa Operacyjna Bielsko) under gen. Mieczysław Boruta-Spiechowicz (on September 3 renamed to Operational Group „Boruta”) (Grupa Operacyjna Boruta)
10. Operational Group „Czersk”
    Czersk Operational Group
    Czersk Operational Group was an Operational Group of the Polish Army. Formed in 1939 under the name of Tuchola Detachment as part of the Intervention Corps created in order to counter a possible German action in the Free City of Danzig, it was not disbanded after the end of the Danzig Crisis...
    
     (Grupa Operacyjna Czersk) under gen. Stanisław Grzmot-Skotnicki
11. Operational Group „Koło” (Grupa Operacyjna Koło) under gen. Edmund Knoll-Kownacki
    Edmund Knoll-Kownacki
    Gen.bryg. Edmund Stanisław Knoll-Kownacki was a Polish military officer and a high-ranking commander of the Polish Army.-Youth:...
    
     (on September 6 renamed to Operational Group „Knoll-Kownacki”) (Grupa Operacyjna Knoll-Kownacki)
12. Operational Group „Piotrków
    Piotrków
    Piotrków may refer to the following places in Poland:*Piotrków Trybunalski, a city in Piotrków County, Łódź Voivodeship*Piotrków Kujawski, a city in Gmina Piotrków Kujawski in Radziejów County, Kuyavian-Pomeranian Voivodeship...
    
    ” (Grupa Operacyjna Piotrków) under gen. Wiktor Thommée
    Wiktor Thommée
    Wiktor Thommée was a Polish military commander and a Brigadier General of the Polish Army. A veteran of the Great War and the Russian Civil War, he is best known for his command over Piotrków Operational Group and the battle of the Bzura during the Polish Defensive War of 1939.- Early life :Wiktor...
    
     (on September 6 renamed to Operational Group „Thommée”) (Grupa Operacyjna Thommée)
13. Southern Operational Group (Południowa Grupa Operacyjna) under gen. Stanisław Skwarczyński)
14. Northern Operational Group (Pólnocna Grupa Operacyjna) under gen. Jan Kruszewski
15. Operational Group „Sieradz
    Sieradz
    Sieradz is a town on the Warta river in central Poland with 44,326 inhabitants . It is situated in the Łódź Voivodship , but was previously the eponymous capital of the Sieradz Voivodship , and historically one of the minor duchies in Greater Poland.It is one of the oldest towns in Poland,...
    
    ” (Grupa Operacyjna Sieradz) under gen. Franciszek Dindorf-Ankowicz
16. Operational Group „Śląsk” (Samodzielna Grupa Operacyjna Śląsk) under gen. Jan Jagmin-Sadowski
    Jan Jagmin-Sadowski
    Jan Jagmin-Sadowski , was a general of the Polish Army, having served in World War One as a member of Józef Piłsudski's legions, as well as commanding Polish forces during the invasion of Poland in 1939....
    
     (on September 3 renamed to Operational Group „Jagmin” (Grupa Operacyjna Jagmin))
17. Eastern Operational Group (Wschodnia Grupa Operacyjna) under gen. Mikołaj Bołtuć (on September 9 renamed to Operational Group „Bołtuć”) (Grupa Operacyjna Bołtuć)

In addition, during the Invasion of Poland

Invasion of Poland (1939)

The Invasion of Poland, also known as the September Campaign or 1939 Defensive War in Poland and the Poland Campaign in Germany, was an invasion of Poland by Germany, the Soviet Union, and a small Slovak contingent that marked the start of World War II in Europe...

 in 1939, several other corps-sized units were formed or improvised. All of them were named after their commanding officers:

1. Operational Group Dreszer (Grupa Operacyjna Dreszer) under Rudolf Dreszer
2. Operational Group Orlik-Łukoski (Grupa Operacyjn Orlik-Łukoski) under Kazimierz Orlik-Łukoski
3. Operational Group Grzmot-Skotnicki (Grupa Operacyjna Grzmot-Skotnicki) under Stanisław Grzmot-Skotnicki
4. Operational Group Kareszewicz-Tokarzewski (Grupa Operacyjna Karaszewicz-Tokarzewski) under Michał Karaszewicz-Tokarzewski
5. Operational Group Zaulauf under (Grupa Operacyjna Zulauf) Juliusz Zulauf
   Juliusz Zulauf
   Juliusz Zulauf was a Polish Army major general . A recipient of the Virtuti Militari, he fought with distinction during World War I, the Polish-Ukrainian War, the Polish-Soviet War, and the 1939 invasion of Poland.Juliusz Zulauf was born in Lwów, then the capital of Austro-Hungarian Galicia...
   
   

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