"Next year, the representatives of European states will meet here to remind the world and their people of the events of 1939," Tusk said during the ceremonies.
The 70th anniversary of the Second World War in 2009 will coincide with the 20th anniversary of the demise of communism in Poland and central Europe in 1989. Memories of war remain strong in Poland. Current estimates suggest some five million Polish citizens died during the war, including three million Jews. Polish history books have long claimed six million victims of the war.
Following the end of the war in 1945, the four World War II Allies shifted Poland's borders to the west, giving it eastern German territories while the Soviet Union absorbed the northern part of Germany's East Prussia region and pre-war eastern Polish territories which now belong to Belarus and Ukraine.
Attacked by Nazi Germany from the west on September 1, 1939, Poland was invaded from the east by the Soviet Union a few days later, on September 17. The two totalitarian powers carved up Poland under the Molotov-Ribbentrop Pact, a secret agreement concluded between Nazi German dictator Adolf Hitler and Soviet leader Joseph Stalin.