First Polish Army ( 1944 – 1945 ) The Polish First Army ( , 1 AWP for short , also known as Berling ' s Army ) was a Polish Army unit formed in the Soviet Union in 1944 , from the previously existing Polish I Corps as part of the People ' s Army of Poland ( LWP ) , a formation of the Polish Armed Forces in the East . The First Army fought westward , subordinated to the Soviet 1st Belorussian Front , during the offensive against Germany that led to the capture of Berlin in May 1945 . Formation . The First Army was formed in the Soviet Union in 1944 , from the previously existing Polish I Corps as part of the People ' s Army of Poland ( LWP ) . On 10 August 1943 , the Soviets gave permission for enlarging the Polish 1st Tadeusz Kościuszko Infantry Division into a Corps ( Polish I Corps ) . The new formation was to be composed of 2 infantry divisions , one artillery and one armor brigade , one support and one air regiment , four independent battalions , and support units . On 29 July 1944 the Polish units were reorganized into the 1st Polish Army . From October 12 to 14 , 1943 , the First Polish Infantry Division made an assault on Lenino near Smolensk and sustained twenty - five percent losses . Later , the 1ST Kosciuszko Infantry Division fought in Berlin around the Reich Chancellery and the Reichstag . At this stage of the war , the Polish role in the Soviet drive westward was fairly substantial , contributing 200 , 000 troops ; this was approximately ten percent of the force taking part in Zhukov ' s and Koniev ' s drive on Berlin . Personnel . The personnel of the Polish First Army were Polish recruits that volunteered after they had been deported into the USSR after its stabilization of eastern Poland following the Soviet invasion of Poland from Nazis . 39 % of officers and technical specialists assigned to the 1st Army were Soviets , while for senior officers the proportion reached 75 % . It was commanded by Lt . Gen . Zygmunt Berling , his second - in - command ' Lt . Gen . Karol Świerczewski , and Col . Włodzimierz Sokorski . The corps took part in combat from September 1943 . Operational history . It operated under the auspices of the Red Army . It first entered combat in the summer of 1944 as part of the 1st Belorussian Front on the right wing of the Lvov - Sandomierz Operation , fighting in the battles during the Soviet crossing of the river Vistula around Dęblin and Puławy . In September 1944 it was involved in heavy fighting while crossing the Vistula river near Praga on the outskirts of Warsaw , during the offensive against Germans that lead eventually to the capture of the Reichstag in Berlin in May 1945 . In January 1945 it took part in the Vistula – Oder Offensive , and afterwards it moved towards Bydgoszcz . The Polish First Army then fought in Pomerania , breaking through the Pomeranian Wall ( " Pommernstellung " ) fortified line and capturing Fortress Kolberg , a heavily fortified city , in March . Its units advanced northeast as far as Gdańsk and Kępa Oksywska . During the battles to penetrate the Pomeranian fortifications , the 1st " Warsaw " Cavalry Brigade made the last mounted charge of Polish cavalry at the village of Schoenfeld . In the spring of 1945 the army , now numbering 78 , 556 soldiers , was redeployed to the front on the Oder river in preparation for the final Soviet offensive of the war in Europe . The Polish Second Army also entered the line of battle at this time , and together the two armies contributed about 10 % of the total forces involved in the operation . During the offensive it crossed the river on April 16 and joined the Battle of Berlin . In it , among other actions , Polish units of the 1st Army crossed the Hohenzollern Canal and advanced on Kremmen , Flatow , Paaren and Nauen . They ended their campaign by participating in the Battle of Berlin . In the Berlin Offensive , the First Polish Army ' s strength was over 74 , 000 , thus making up 7 . 5 % of the strength of the Soviet 1st Belorussian Front , which counted over 980 , 000 men when the Polish First Army is included in the total . During the Berlin Offensive , the Polish First Army sustained casualties of over 10 , 400 men . The troops of the 1st Infantry Division supported by the 2nd Howitzer Artillery Brigade and the 1st Independent Mortar Brigade , fought in Berlin around the Technical University and the southwestern side of the Tiergarten close to the zoo . The army was disbanded after the war on August 22 , 1945 . Its constituent units went on to serve in the armed forces of the newly created Polish People ' s Republic . Organization . The 1st Polish Army was very similar in organisation to other standard general purpose armies making up the bulk of Red Army ' s order of battle . It had a good mix of infantry units and artillery together with other support arms . Its armor capability was considerably weaker , and consisted of only one organic tank brigade . In manpower it was broadly equivalent to an American infantry corps , having a strength of 74 , 530 men on May 1 , 1945 . At the end of the war in 1945 , it consisted of the following large units ( honorific names given in brackets )