In Poland, the President Lech Kaczynski and Prime Minister Donald Tusk along with diplomats paid tribute to the victims. German Chancellor Angela Merkel and Russian Prime Minister Vladimir Putin are also expected to join the leaders later in the day.
"We are here to remember who in that war was the aggressor and who was the victim, for without an honest memory neither Europe, nor Poland, nor the world will ever live in security," Polish Prime Minister Donald Tusk was quoted as saying in a news agency report.
On Sep 1, 1939, the German battleship, Schleswig-Holstein fired on a Polish base on the Baltic sparking off the second World War. WW II, the most wide spread war that the world has ever seen was fought between two military alliances the Allies and the Axis.
The war claimed almost 50 million lives including six million Jews who perished in the 'Holocaust' launched by Adolf Hitler.