I have never heard of the Spanish Blue Division!
Although Spanish leader Field Marshal (Generalísimo) Francisco Franco did not enter the war on the side of Nazi Germany, he permitted volunteers to join the German Army (Wehrmacht Heer) on the clear and guaranteed condition they would fight exclusively against Bolshevism (Soviet Communism) on the Eastern Front, and not against the Western Allies or any Western European occupied populations. In this manner, he could keep Spain at peace with the Western Allies whilst simultaneously repaying Hitler for his support during the Spanish Civil War (see Condor Legion). Spanish foreign minister Ramón Serrano Súñer made the suggestion to raise a volunteer corps, and at the commencement of Operation Barbarossa, Franco sent an official offer of help to Berlin.
Hitler approved the use of Spanish volunteers on June 24, 1941. Volunteers flocked to recruiting offices in all the metropolitan areas of Spain. Cadets from the officer training school in Zaragoza volunteered in particularly large numbers. Initially, the Spanish government was prepared to send about 4,000 men, but soon realized that there were more than enough volunteers to fill an entire division: 18,104 men in all, with 2,612 officers and 15,492 soldiers.
Aviator volunteers formed a Blue Squadron (Escuadrillas Azules) which, using Bf 109s and FW 190s, was credited with 156 Soviet aircraft kills.
The Blue Division faced a major Soviet attempt to break the siege of Leningrad in February 1943, when the Soviet Army 55, reinvigorated after the epic victory at Stalingrad, attacked the Spanish positions at the Battle of Krasny Bor, near the main Moscow-Leningrad road. Despite heavy casualties, the Spaniards were able to hold their ground against a Russian force 7 times larger and supported by tanks. The assault was contained and the siege of Leningrad was maintained for a further year. This victory established the reputation of the Blue Division with the German general staff. It remained on the Leningrad front where they suffered heavy casualties both due to cold and to enemy action. Franco dispatched more reinforcements, which in time included conscripts in addition to volunteers.
Through rotation, as many as 45,000 Spanish soldiers served on the Eastern Front.
The casualties of the Blue Division and its successors included 4,954 men killed and 8,700 wounded. Another 372 members of the Blue Division, the Blue Legion, or volunteers of the Spanische-Freiwilligen Kompanie der SS 101 were taken prisoner by the victorious Red Army; 286 of these men were kept in captivity until April 2, 1954, when they returned to Spain aboard the ship Semiramis, supplied by the International Red Cross.
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.
That was generally the case for all non-German Waffen SS volunteers from Western Europe.