Question

What was the main reason Britain entered the war

Answer 1

For ww1 Germany walked all over Belgium instead of fighting the French
For ww2 hitler kept ordering troops to break agreements that wear sighned in the treaty of versia then they made Britain mad when they made the same mistake as the last war

Answer 2

it was an ally of france. because germany invaded neutral belgium. because it supported slavic nationalism.

Hope this Helps :D