Although the poem does not describe Elegast’s background, he was an old friend of Charlemagne that had fallen into disgrace, and his banishment to the forest and his name connotes he was elven. Elegast could put people to sleep magically, could open locks without keys, and has a magic herb that when he puts in his mouth allows him to talk to animals. He lived in the forest, thief to the rich people and kind to poor people.
Source: Elegast – Wikipedia
Tim B.
“According to Low German legends, Elbegast was a dwarf who could steal eggs from under birds.[3]”
Tim B.
see also: Alberich