Historical Background:
A Star of David, often yellow-colored, was used by the Nazis during the Holocaust as a method of identifying Jews. After the German invasion of Poland in 1939 there were initially different local decrees forcing Jews to wear a distinct 
sign – in the General Government e.g. a white armband with a blue Star of David on it, in the Warthegau a yellow badge in the form of a Star of David on the left side of the breast and on the back. The requirement to wear the Star of David with the word Jude (German for Jew) inscribed was then extended to all Jews over the age of 6 in the Reich and the Protectorate of Bohemia and Moravia (by a decree issued on September 1, 1941 signed by Reinhard Heydrich ) and was gradually introduced in other German-occupied areas, where local words were used (e.g. Juif in French, Jood in Dutch).
Jewish inmates in concentration camps were later forced to wear similar Nazi concentration camp badges.
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