In point of fact many non-German troops from all over Europe fought on the Axis side, the largest non -German armies were the Italians, Romanians, and Hungarians. They played mostly a support role. Not nearly as well armed or well trained as the Wehrmacht, the helped occupy vast swaths of Soviet territory and flank rapidly advancing German armored divisions. Other European nations, mostly from Nazi occupied countries also sent in volunteers to fight on the Axis side including countries such as Belgium, Denmark, the Netherlands, France, Norway, and Slovakia. Finland also fought the Soviets as they were attacked by the USSR and wanted to reclaim some of their territory. In addition to all of this, many Soviet defectors, over a million in fact, also fought along side the Axis on the Eastern Front, mostly in support roles. Even more interesting is the fact by the end of WWII, the super elite Waffen SS was more than half non-German. Himmler recruited Waffen SS troops all over Nazi-occupied Europe. The primary motivation for these non-German troops volunteering on the Eastern Front was their staunch opposition to Communism-—this of course included Spain’s Blue Division. Himmler even recruited a Muslim division from Bosnia-Herzgovina. So much for the Aryan myth.
The Nazis persecuted Jews and Christians but were OK with Muslims and other non-Judeo-Christian religions.
So much for the Aryan myth.
With the best of the Nazi Aryan stock having been converted into organic fertilizer across Europe, primarily in the East, the Nazi's had to meet SS manpower needs somehow. By 1943, so many Waffen SS men had gone on to Valhalla that the formerly volunteer Waffen SS began conscripting.