In 955, when Konrad I ruled in Germany, the Hungarians were stopped near Augsburg and two leaders, Lehel and Bulcsú were captured. When they were taken to the emperor to choose their kind of death Lehel asked for his bugle and said he'd blow it first and then tell them. So they took it to him but he, instead of blowing it, knocked the emperor off with it so that he died. It's cause according to the Hungarian belief the ones you killed in your life would serve you in the other world.
So that's why the bugle is broken, as you can see.
