Þiðrekssaga

The Gothic King Theoderic the Great was remembered in Germanic legend as Dietrich von Bern (Bern is the Middle High German name for Verona, where Theoderic had one of his residences). Dietrich figures in a number of surviving works, and it must be assumed that these draw on long-standing oral tradition. The majority of poems about Dietrich/Theoderic are composed in Middle High German, and are generally divided by modern scholars into historical (German: historische Dietrichepik) and fantastical (German: either märchenhafte or aventiurehafte Dietrichepik). The historical poems can loosely be connected with the life of the historical Theoderic and concern his expulsion from Verona by his uncle Ermenrich (Ermanaric) and his attempts to regain his kingdom with the help of Etzel (Attila). The fantastical poems concern his battles with dwarfs, dragons, giants, and other mythical beings, as well as other heroes such as Siegfried. In addition to these two categories of poems, he appears as a supporting character in some poems such as the Nibelungenlied and Biterolf und Dietleib.

Despite the identification of Dietrich von Bern with Theoderic the Great throughout the entire Middle Ages, the two figures are vastly different. As the Encyclopædia Britannica (1911) states: "the legendary history of Dietrich differs so widely from the life of Theoderic that it has been suggested that the two were originally unconnected." The most noticeable differences are:

Numerous theories have been proposed to explain these differences. The change from invader to exile is sometimes explained as an attempt to justify Theoderic's taking possession of Italy. Attila and Ermanaric as contemporaries is part of synchronization, a phenomenon frequently encountered in oral traditions. This can also be seen in the way that other heroes such as Wayland and Witige have been drawn onto stories about Dietrich.

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Wikipedia