World War 1 and World War 2
World War 1.
The Germans fought for the Central Powers in World War I.
They fought the Germans, Japanese, and Italy
In the early years of World War One the Germans, Austrians, Hungarians and Serbians and the French fought in the war.
In a way, yes. German immigrants and decendants of German immigrants in other countries fought against the Nazis in World War II.
The Germans, Japan, and Italy.
The Americans fought the Germans and the Italians in WW2.