Weichsel-Oder-Operation
On 17 January 1945 – after the beginning of the Vistula–Oder Offensive of the Red Army – Soviet troops and Polish troops of the First Polish Army entered the ruins of Warsaw, and liberated Warsaw's suburbs from German occupation. The city was swiftly taken by the Soviet Army, which rapidly advanced towards Łódź, as German forces regrouped at a more westward position.