Another commemoration took place in Westerplatte, a peninsula that is now known as the city of Gdansk, which was shelled heavily by German battleships. That event was attended by Polish Prime Minister Mateusz Morawiecki and European Commission Vice-President Frans Timmermans.

While Poland has received an apology from Germany, it has not yet benefitted from monetary compensation, something it continues to claim from its wealthy neighbor.

Morawiecki has recently reiterated the demand for reparations, a matter Berlin says is settled.

"We need to talk about those losses, we need to remember, we need to demand truth and demand compensation," Reuters quoted Morawiecki as saying.

Bloomberg reported on Sunday that a Polish special parliamentary group published a preliminary study earlier this year that shows the war may have cost the Polish economy more than $850 billion.

DW said few places suffered the "level of death and destruction" seen in Poland during World War II, where around one-fifth of the population perished during more than five years of occupation.

After the war, Poland was occupied by its liberator, the Soviet Union, and remained under its control until 1989.

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