World War II: Soviet forces invade Austria and capture Vienna. Polish and Soviet forces liberate Danzig.

The Workers' and Peasants' Red Army, often shortened to the Red Army, was the army and air force of the Russian Soviet Republic and, from 1922, the Soviet Union. The army was established in January 1918 by a decree of the Council of People's Commissars to oppose the military forces of the new nation's adversaries during the Russian Civil War, especially the various groups collectively known as the White Army. In February 1946, the Red Army was renamed the "Soviet Army". Following the dissolution of the Soviet Union it was split between the post-Soviet states, with its bulk becoming the Russian Ground Forces, commonly considered to be the successor of the Soviet Army.

The Vienna offensive was an offensive launched by the Soviet 2nd and 3rd Ukrainian Fronts in order to capture Vienna, Austria, during World War II. The offensive lasted from 16 March to 15 April 1945. After several days of street-to-street fighting, the Soviet troops captured the city on 13 April 1945.

The People's Army was a communist partisan force of the Polish Workers' Party (PPR) active in Occupied Poland during World War II from January to July 1944. It was created on the order of the Soviet-backed State National Council to fight against Nazi Germany and support the Red Army against the German forces in Poland.

The East Pomeranian strategic offensive operation was an offensive by the Soviet Red Army against the German Wehrmacht on the Eastern Front. It took place in Pomerania and West Prussia from 10 February – 4 April 1945.