Nibelungen

The German Nibelungen – with the corresponding Old Norse form Niflung (Niflungr; pl. Niflungar) – is the name in Germanic and Norse mythology of the royal family or lineage of the Burgundians who settled in the early 5th century at Worms.

The vast wealth of the Burgundians is often referred to as the Niblung or Niflung hoard. In some German texts Nibelung appears instead as one of the supposed original owners of that hoard, either the name of one of the kings of a people known as the Nibelungs, or – in variant form Nybling – as the name of a dwarf. In Richard Wagner's opera cycle Der Ring des Nibelungen (1848–1874), Nibelung denotes a dwarf, or perhaps a specific race of dwarfs.

The earliest probable surviving mention of the name is in the Latin poem Waltharius, believed to have been composed around the year 920. In lines 555–6 of that poem Walter, seeing Guntharius (Gunther) and his men approaching says (in the text, usually taken to be the oldest):

Nōn assunt Avarēs hīc, sed Francī Nivilōnēs,
cultōrēs regiōnis.

The translation is: "These are not Avars, but Frankish Nivilons, inhabitants of the region." The other texts have nebulones 'worthless fellows' instead of nivilones, a reasonable replacement for an obscure proper name. In medieval Latin names, b and v often interchange, so Nivilones is a reasonable Latinization of Germanic Nibilungos. This is the only text to connect the Nibelungs with Franks. Since Burgundy was conquered by the Franks in 534, Burgundians could loosely be considered Franks of a kind and confused with them. The name Nibelunc became a Frankish personal name in the 8th and 9th centuries, at least among the descendants of Childebrand I (who died in 752, see Dronke, p. 37). Yet, in this poem, the center of Gunther's supposedly Frankish kingdom is the city of Worms on the Rhine.

...
Wikipedia