Mainly because Hitler wanted to invade Russia, and Poland lay between Russia and Germany. Hitler could not get to Russia without passing through Poland, so invading Poland was the easiest option.Here is a map of Europe in 1939 to show this.The Big orange area called the 'Union of Soviet Socialist Republics' is Russia.That is just another name for Russia http://www2.bc.edu/~heineman/maps/1939la...itler could not get to Russia without passing through Poland, so invading Poland was the easiest option.Here is a map of Europe in 1939 to show this. The Big orange area called the 'Union of Soviet Socialist Republics' is Russia.