First I will compare the Territorial size of some nationsGermany (1937)=183,276 mi^2
Germany (1945)=137,822 mi^2
Poland (1937)=149,965 mi^2
Poland (1945)=121,757 mi^2
Romania (1937)=113,919 mi^2
Romania (1945)=91,699 mi^2
Bulgaria (1937)=39,825 mi^2
Bulgaria (1945)=42,855 mi^2
Lithuania (1937)=21,330 mi^2
Lithuania (1945)=25,212 mi^2
Now for Deported/Murdered Civilians (1943-1947) from historic territories taken over by Russia or it's puppets
Germany-12,400,000 deported of whom 2,630,000 were killed
Poland-8,495,000 deported of whom 3,380,000 were killed
Romania-1,654,000 deported of whom 215,000 were killed
Japan-1,000,000 deported, few killed
Bulgaria-790,000 deported of whom 103,000 were killed
Finland-450,000 deported few killed
Austrians from former Austrian Lands=4,900,000 of whom 850,000 were killed
Also, information on the changing size of the nations can be found at: http//www.library.uu.nl/wesp/populstat/populhome.html
I hope this helps
Stephen