Once Russia was invaded by Germany on June 22nd, 1941, General Franco and his government decided to thank the Reich for his decisive support during the bloody Spanish Civil War, especially when the city of Guernica was bombed by the planes of the Condor Legion, an action that took the lives of 1 600 people and destroyed the whole city.
As the result of a recruiting campaign all over Spain, about 18 000 volunteers joined the Blue Division (blue because supporters of the Spanish Falangist wore blue shirts) and headed towards the Russian Front to “fight communism” along with the Wermacht. The last contingent of the Blue Division was repatriated to Spain in 1944. Some 4 000 never returned though.
After the fall of the Reich, Spain was not considered a defeated state and joined NATO. El Caudillo Franco was never tried and ruled his country with firm hand until his death in 1975.