We should retain only those elements of te story which are found also in Italy -- Andrea da Barberino, "Guerino il Meschino" (1391) -- Antonio dlla Sale, "Salade" ("Il monte della Sibilla") -- the latter locates the "Monte della Sibillia" in the Appenines near NORCIA.

Speranza

we have left only those elements of the story which are also found in Italy, and found there earlier than in Germany:

the tale of a knight who is enticed into a palace of sensual delights where a queen reigns over crowds of beautiful girls, and whose remorse leads him to abandon the palace and seek atonement.

Of this Italian story we have two main versions.

(a) the Guerino il Meschino of Andrea da Barberino, written in 1391.

(b) the later account given in the Salade of Antonio della Sale of a visit to the Monte della Sibilla in the Apennines near Norcia, where the legend had become localized. 

Antonio della Sale represents the story as current among the peasantry of the district, and we have other evidences of the wide fame of this mountain as the abode of a supernatural being. 

The journey to seek absolution from the Pope URBANO IV is found in both versions.

In Andrea da Barberino's version, the repentant sinner is successful.

The repentant is NOT successful in Antonio della Sale's version. 

In Guerino il Meschino the divinity still retains much of the Sibylline character, for the hero goes to seek her in her capacity as a revealer of the unknown. 

He resists her enticements to remain, and absolution is granted him because he thus overcomes temptation. 

In the version in the Salade, the Pope URBANO IV at first refuses absolution in order to emphasize the greatness of the offence, and only yields when the knight, hopeless of salvation for his soul, has returned to the mountain to make the most of what remains of the life of the body. 

The incident of the budding staff as cause of the Pope's repentance appears first in Germany -- a typical anti-Catholical trait: since it's God that saves Danhuser's soul (it is a miracle) rather than the Pope, who, most German versions have it, gets condemned for eternity for not granting pardon to a sinner (which goes against the church canon). 

But all this matter of absolution is quite clearly the result of church and anti-Catholic-church influence. 

Laying that aside, we have the legend in its original pagan form. 

This form G. Paris is inclined to regard as of Celtic origin and as having reached Germany from the Celtic west by way of Italy. 

It belongs, he conjectures, to the group of beliefs about a happy other-world which appear very widely in folk-tales, especially in those countries that have come under Celtic influences.

Thus we are able to account for the quasi Court of Love elements in the Tannhauser story on grounds altogether remote from mediaeval love-allegory