Theodoric of Bern is hardly a genuine hero of the Nibelung, being really the main figure in a cycle of Germanic romances of his own; but as he, under the abbreviation Dietrich, is brought in to play a considerable part in the final action of the tale, this seems the fittest place for treating of him and the names in connection with him.
    He seems to have been brought into the Nibelungenlied because the Germanic mind could conceive of nothing considerable passing without him.  He is represented as one of the four-and-twenty princes in King Etzel's train, and as anxious to prevent mischief to the visitors from Burgundy, warning them of Chriemhilt's enmity, and refusing to attack them at her request.  When the great slaughter began, it was Dietrich who conveyed the king and queen safely out of the mêlée, and withheld his men from engaging in it, until almost at the end, when they could no longer be restrained, and rushing into the fray were all slain except old Sir Hildebrand, though on the other hand, Gunther and Haghen alone remained alive of the Burgundians.  Dietrich then armed himself, and after a fierce combat, made them both prisoners, and delivered them up to Chriemhilt, fully intending that she should spare their lives; but when her relentless fury had fallen on them, he assisted King Etzel to bury the dead, and to return the horses and armour of their fallen champions to their respective countries.
    Other German romances, however, elevate this prince to a much higher rank.  The Book of Heroes, written by Wolfram of Eschenbach and Heinrich of Ofterdingen, makes Dietrich of Bern, in Lombardy, son of King Dietmar.  Hearing of Chriemhilt's rose garden, which measured seven miles round, and was guarded by twelve champions, he was seized with a desire to do battle with them, for love of battle, not of ladies, though the victor was to receive a chaplet of roses and a kiss from the young lady.  The wise old Sir Hildebrand, of the Wolfing line, conducted him and his eleven companion champions to Wurms, where the single combats took place.  Dietrich's knights were successful, and for the most part took the chaplets, but refused the kisses, because they disdained Chriemhild as a faithless maiden. (History of Christian Names, Yonge, 1884)