So basically, France and poland were allies/friends before ww2 and france said that if poland was ever invaded by germany that it would mean war. Despite this, when poland was actually invaded on september 1st 1939, France did eventally declare war on Germany but they didnt do much to help Poland. But after a while Germany turned their eyes toward France and now they were being invaded just like poland.
These are not the current designs for these charecters. These were their designs in world war 2. After the war they look a bit more mature and both poland and france stop wearing short sleeves after the war and switch to more long sleeved outfits which is actually a very important sybolism and there is a reason why they changed to long sleeves.