It became known as the Polish II Corps and went on to fight Nazi German forces in the Italian Campaign, including the Battle of Monte Cassino.
From Poles who remained in the Soviet Union, the Polish 1st Tadeusz Kościuszko Infantry Division was formed in May 1943.
Together they constituted the Polish People's Army (Ludowe Wojsko Polskie, LWP); it fought on the Eastern Front under Soviet command all the way to the Battle of Berlin.
The new formation became known as Anders' Army and started to organise in the Buzuluk area, by recruiting from NKVD camps for Polish POWs.
It conducted political activities and organized large-scale social welfare and relief programs for Polish communities in the Soviet Union.
The division with its supporting elements was sent to the Eastern Front in September 1943 and its first major engagement was the Battle of Lenino.
Subsequent Soviet-created Polish army units on the Eastern Front included the Second (1945) and Third Polish Armies (the latter was quickly merged with the Second due to recruitment problems); the smaller formations included 10 infantry divisions (numbered from 1st to 10th) and 5 armoured brigades.
Special political officers, almost exclusively made up of Soviets, oversaw the Polish soldiers.
The Soviets also created political military police, which later became the Main Directorate of Information of the Polish Army (Główny Zarząd Informacji Wojska Polskiego).
Later it took part in the Prague Offensive, which was the last major Soviet operation of World War II in Europe.