The Polish exile government was located in London. The Polish

paratroopers were as tough as the British counterpart (Operation Market Garden for instance). The Polish army fought along with the Russians on their way to Berlin. In general, the Polish soldiers were deployed to the major Allied forces as detachments.

The French army here were referred to Free French Force led by General de Gaulle not Vichy French governement.

I believe that this parade is the celebration on the victory on Nazi Germany. Since China wasn't involved in the Europe theater, China was left out.