Commemoration of a field service held by 1200 Jewish soldiers protected by their gentile comrades on Yom Kippur of 1870 during the siege of Metz in the Franco-Prussian war played an important role among German Jews as a symbol of acceptance and integration into the society as citizens with equal rights. Based on a short note in several newspapers it became very fast a very common commemoration among Jews. But it was a pious fraud of an act that never happened in the described way. Although this was known and already published in late 1870 it did not hamper the spreading. In recent years this tradition of commemoration was revitalized. This time even in combination with a wrong date: the day when the French garrison of Metz surrendered. Moreover, it is described even by officials as an act of traditional religious tolerance in the German armed forces.