heroic figure of Germanic legend, apparently derived from Theodoric the Great (Theodoric), an Ostrogothic king of Italy who reigned from c. 493 to 526 AD.

Dietrich's exploits are related in a number of south German songs preserved in Das Heldenbuch (“The Heroes Book”)—including Dietrichs Flucht (“Dietrich's Flight”), Die Rabenschlacht (“The Battle of Ravenna”), Alpharts Tod (“Alphart's Death”), and a number of additional stories—and, more fully, in the 13th-century Icelandic prose Thidriks saga. This legend also has a connection with the Middle High German epic Nibelungenlied.

Driven by Ermenrich ( Ermanaric) from his kingdom of Bern (Verona), Dietrich lives for many years at the court of Etzel (Attila), until he returns with a Hunnish army to defeat Ermenrich at Ravenna. Etzel's two sons fall in the fight, and Dietrich returns to Etzel to answer for their deaths. Later he has his revenge by slaying Ermenrich. Dietrich's long stay with Etzel represents Theodoric's youth spent at the Byzantine court. The exile is adorned with amazing exploits, most of which have no connection with the cycle.

Dietrich typifies the wise and just ruler as opposed to the tyrannical Ermenrich. Many of the incidents told about him have no basis in the story of Theodoric, although some could be related to the experiences of Theodoric's father, Theodemir. Other figures in the Dietrich cycle are his weapons master, Hildebrand, with his nephews Alphart and Wolfhart; Wittich and Heime, Dietrich's traitorous vassals; and Biterolf and Dietleib, the king of Toledo and his son, who join Dietrich in battle at Worms.