In August 1939, after failed attempts to conclude anti-Hitler pacts with other major European powers, Stalin entered into a non-aggression pact with Nazi Germany that divided their influence and territory within Eastern Europe, resulting in their invasion of Poland in September of that year, but Germany later violated the agreement and launched a massive invasion of the Soviet Union in June 1941. Despite heavy human and territorial losses, Soviet forces managed to halt the Nazi incursion after the decisive Battles of Moscow and Stalingrad. After defeating the Axis powers on the Eastern Front, the Red Army captured Berlin in May 1945, effectively ending the war in Europe for the Allies.[6][7] The Soviet Union subsequently emerged as one of two recognized world superpowers, the other being the United States.[8] The Yalta and Potsdam conferences established communist governments loyal to the Soviet Union in the Eastern Bloc countries as buffer states. He also fostered close relations with Mao Zedong in China and Kim Il-sung in North Korea.