Because of the increasing numbers of foreign volunteers coming from all over Europe, the Germans authorized and issued national insignia to be worn on Werhmacht uniforms.
The German Army and Waffen-SS had by far the strongest foreign volunteer contingent and therefore a greater number of national insignia. During the early stages of Operation Barbarossa many of these foreign contingents wore their own home made insignia to distinguish their nationality. Eventually German regulations prohibited their used but it was never enforced.

In 1941, many of the volunteers from Denmark, Flanders, Holland and Norway formed their own foreign legions under the auspices of the Waffen-SS.
These SS legionnaires wore their own national arm shields that were made in their respective countries. The shields range in size, material and shape.
Foreign volunteers from France, Walloon and Spain were placed under the jurisdiction of the German Army and wore German made machine woven shields commonly referred as "BeVo" stylebecause they were made by the "Bevo- Wuppertal" firm, which used to manufacture many foreign legion insignia.

From axis101.bizland.com