The main countries are: Britain (UK), USA (Later in the war), and France. Those are the only ones I remember but there are a lot of other countries.
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Plus the Soviet Union (USSR). About 75% of all German soldiers killed in World World 2 were killed on the Eastern Front, fighting the Soviet Union. This tends to get overlooked.
Auschwitz (the largest concentration camp, located in Poland) The Allies (the countries Canada, U.S.A., Great Britain, France, who fought against Germany) Adolf Hitler (the leader of Nazi Germany at the time)
Germany and the United Kingdom
Nazi Germany was under Nazi German control during the Holocaust.
You have it the wrong way round. Germany WAS Nazi, and their armies occupied most of the countries in Europe.
Nazi Germany
The Axis forces. These countries were led by Nazi Germany, but countries such as Italy, Greece, Austria, and Romania also fought against them.
Russia
It was the nazi war fought in Poland, Germany, all those countries
Nazi Germany .
Nazi Germany and Japan .
Auschwitz (the largest concentration camp, located in Poland) The Allies (the countries Canada, U.S.A., Great Britain, France, who fought against Germany) Adolf Hitler (the leader of Nazi Germany at the time)
Australia fought with Great Britain and her ally the USA. They fought against the Japanese Empire and Nazi Germany but the majority of Australia's fighting was based in the Pacific.
Germany and the United Kingdom
Germany led by the Nazi Party and Adolf Hitler, Italy led by Mussolini and Japan, their leader was pretty much General Tojo.
Nazi Germany , Japanese , Afghanistan ,
This is hard to say because many, if not all, the countries had absolutely no clue what the Nazi Party were doing to the Jews. When they found the extermination camps of course all countries were completely shocked. Even many of the German population had no idea of the extermination camps (that's how well hidden and kept Hitler had made them) and American soldiers would take Germans into the camps to show them the extent of what Adolf Hitler, their leader, had done.
The Allies... 2nd edit: (...who were...?)