The Auschwitz concentration camp was liberated by the Soviet Red Army on January 27, 1945. In 1947, the Polish parliament passed legislation to change the museum of the Nazi Holocaust, the Auschwitz-Birkenau National Museum, as a history of infamous crimes during the Nazi German rule in the Second World War. In 1979, UNESCO listed the Auschwitz concentration camp as a World Heritage Site. 

As we can see, A lot of people who learn the language depends on the region of Poland. People who live in Eastern part of Poland are more likely to choose Russian to its usability in that region.There are many businesses in West part of Poland that work together with German clients, or sell goods to Germany. because people who know that German at least their communicative level are on demand.

On this diagram you can how confident people are in the top 6 foreign language.
Dark Green - Fluent
Green - Good
Light Orange - Basic
Orange - Only basic words
Red - Lack of knowledge

During the Second World War, Sikorski became the Prime Minister of the Polish government in exile, and the Commander-in-Chief of the Polish Army was a strong supporter of Polish diplomacy. He supported the re-establishment of diplomatic relations between Poland and the Soviet Union. The relations between Poland and the Soviet Union signed the Soviet-German non-aggression treaty in Molotov and Ribbentrop, and the Germans were seriously damaged when they launched the Polish campaign. Because Sikorsky insisted that the International Red Cross investigate the Katyn massacre, Soviet leader Joseph Stalin announced in April 1943 that he would sever the relations between Poland and the Soviet Union.

 Sikorski had been the most prestigious leader of the Polish exiles, and his death was a severe setback for the Polish cause.