"Merlin Enthralled" is from Richard Wilbur's 1956 poetry collection Things of This World, a book that was awarded both a Pulitzer Prize and a National Book Award. The poem offers a new look at the ancient legend of Merlin, the magician who served as counselor to the legendary King Arthur of England. The episode that Wilbur recounts is from the end of Merlin's life when he falls under a spell cast by Niniane, a sorceress who lulls him to sleep. In most versions, this story ends with Merlin trapped within a tree or cave or tomb where he slowly wastes away in an agonizing death, but, in Wilbur's poem, Merlin lies peacefully beside a lake, becoming one with nature as he dies.

Among this poem's noteworthy aspects is the way it modernizes a traditional story dating back almost a millennium. Arthur, Gawen, and the other knights, who have stood for centuries as figures of military force, are shown to be almost childlike when they cannot find Merlin, while the sorcerer himself seems to be released, rather than captured, by Niniane (the medieval sense of the word "enthrall" entailed holding one in slavery). Wilbur's use of formal elements of rhyme and meter links this work with centuries of poetic tradition, but he uses enough verbal flexibility to make this formal structure nearly inconspicuous. "Merlin Enthralled" is generally considered to be one of the best of Richard Wilbur's early poems, a standout in a career that has lasted for more than fifty years.