He is well known for his poem "Merlin der Zauberer" (“Merlin the Magician,” 1857). Verse epics or narratives in the German Arthurian Literature tradition were undertaken with various success from the mid-18th century forward. In contrast to Romantic poets like Karl Leberecht Immermann for whom Merlin represented the spirit of nature, Müller created a “modern Merlin” who, as Niniane's lover, uses his wisdom to resolve the conflict created by his revelation of the love affair of Guinevere. The Merlin-Niniane relationship is presented as uncharacteristically positive compared to other depictions in the Arthurian cannon.