After the Baltic states were forced to accept treaties, Stalin turned his sights on Finland, confident that Finnish capitulation could be attained without great effort. The Soviets demanded territories on the Karelian Isthmus, the islands of the Gulf of Finland and a military base near the Finnish capital Helsinki, which Finland rejected. The Soviets staged the shelling of Mainila and used it as a pretext to withdraw from the non-aggression pact. The Red Army attacked in November 1939. Simultaneously, Stalin set up a puppet government in the Finnish Democratic Republic.[clarification needed] The leader of the Leningrad Military District Andrei Zhdanov commissioned a celebratory piece from Dmitri Shostakovich, entitled "Suite on Finnish Themes" to be performed as the marching bands of the Red Army would be parading through Helsinki. After Finnish defenses surprisingly held out for over three months while inflicting stiff losses on Soviet forces, the Soviets settled for an interim peace. Finland ceded southeastern areas of Karelia (10% of Finnish territory), which resulted in approximately 422,000 Karelians (12% of Finland's population) losing their homes. Soviet official casualty counts in the war exceeded 200,000, although Soviet Premier Nikita Khrushchev later claimed the casualties may have been one million.