The delay in signing an allied peace treaty, ending the war with Germany, was the Soviet Union.
Stalin wanted to destroy the nation of Germany, while the western allies saw a democratic Germany as essential to defending Europe from the Russians.

actual peace treaty was signed with Germany after WWII by the allied powers.

The collapse of the Berlin Wall on November 9, 1989, was the true end of WWII.

and one could have a nice life time hobby doing scholarly research on the subject.

from 1978-1981 we were still legally considered an 'occupation', according to our Status of Forces agreements.