What is the name of the poem beginning 'Twas brillig, and the slithy toves'?

The poem beginning “‘Twas brillig, and the slithy toves” is “Jabberwocky.” Lewis Carroll published it in his 1871 sequel, Through the Looking-Glass, and What Alice Found There, where Alice discovers it in a book written in mirror writing.

The poem tells of a young hero who sets out to defeat the fearsome Jabberwock. Its language sounds partly familiar and partly invented: words such as “slithy,” “brillig,” “frumious,” and “galumphing” create meaning through sound, context, and suggestion. Carroll called this style nonsense verse, but the poem still has a recognizable narrative, a warning, a quest, a battle, and a triumphant return.

Carroll had written the opening stanza years earlier. In 1855, he printed an early version in Mischmasch, a family magazine, under the title “Stanza of Anglo-Saxon Poetry.” He later expanded it for Through the Looking-Glass. John Tenniel’s illustration of the Jabberwock became the poem’s defining visual image.

“Jabberwocky” is often confused with Carroll’s other poems, including “The Hunting of the Snark” and “The Walrus and the Carpenter,” but its opening line identifies it uniquely.