In 1941 after the rupture of the Ribbetrov-Molotov pact, and the beginning of the Barbarossa operation, with the subsequent invasion of the Soviet Union by the German army, Spain, as part of the commitments made to Germany for its help to the winning side of the civil war, decided to send a division of volunteers to fight exclusively on the eastern front. This division would not be part of the Spanish army, although its cadres and officers were mainly members of the Spanish armed forces. In this way the Spanish government, was unmarked of its position of military ally of the axis.
Therefore, the soldiers of the 250th Infantry Division known as the Blue Division or Spanish Division of Volunteers, wore the German uniform with the only badge of a shield with the flag of Spain on their right sleeve.
This did not happen with the Romanian, Hungarian and Bulgarian divisions, which participated in the same front, wearing the uniforms of their own armies.