But Russia did start the war. They allied with the Nazis to...

But Russia did start the war. They allied with the Nazis to invade and divide Poland.

Soviet invasion of Poland - Wikipedia

The Soviet invasion of Poland was a military conflict by the Soviet Union without a formal declaration of war.On 17 September 1939, the Soviet Union invaded Poland from the east, 16 days after Nazi Germany invaded Poland from the west. Subsequent military operations lasted for the following 20 days and

and they did get a little help via the terrible Murmansk convoys.