Actually, Germany didn't declare war on anyone, the US as last. Hitler's aim was to expand towards the east and not to wage war on any western country. The one that declared war on Germany was the UK. (Which had some more reasons, compare: balance of powers, arms race - and don't look it up here.)
In my opinion, France can be considered the country with the greatest losses out of WW2. This whole section is nothing more than telling others your opinion.
Use history books for info about WWII - not google!