No one cares about the King of Denmark. Or Finland, where Jews prayed on the front lines alongside the Wehrmacht, fighting the Soviets. Wish there were more non-individual examples to cite.
It’s fictional, of course, just like George Washington and the Cherry Tree. The King of Denmark did not go around on a bicycle wearing a Jewish star badge to protest the Nazis. But Leon Uris created the legend, and when legends become facts, you go with the legend. So a tee-shirt with the yellow star and the word Jude or in France Juif on it would serve as a “King of Denmark” protest against anti-Jewish violence such as was perpetrated in Toulouse.