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In German mediaeval tradition, a knight who is enticed by Venus into her cave in the Horselberg, i.e. the hill of Horsel or Ursula. Making his escape, he seeks absolution from Urban IV., who tells him that there is no more chance of forgiveness for him than there is for the budding of the staff in his hand. Tanhaiiser returned to the cave ; the staff budded ; but the knight was sought in vain. In its main features this story is the same as that of Thomas the Rimer, who is allured by the fairy queen to her home in Ercildoune, in which the name Ursula again appears.