This could get political if we're not careful and detract from the topic, but the British Empire was definitely no angel in it's day. Read some Boer accounts of the South African Boer War, or in fact any account from the 'other side' from almost anywhere where there was a British Imperial presence. As for motivations to fight, many didn't have political or freedom ideals. Some, Poles, Czechs, French etc would have wanted revenge, a chance to get back at the Germans and fight for the day that their countries were liberated. Others from all over the British Commonwealth went to war and did their job, played their part in what started as an adventure and turned into a struggle for survival. It's not uncommon to read accounts where people fought for their mates, not for any one ideal, monarch or political theory. As for the Germans, yes there would have been an element of superiority and Nazi indoctrination in some cases, but for the most part I think when you read biographies and personal histories, they were just doing their jobs too. Not all Germans were Nazis. I'm not sure when the world became aware of the extreme plight of European Jews, but they would have known there was anti-Jewish sentiment in Germany at the time. The extent of the atrocities committed against minority races and Russian POW were not fully known until late in the war.