"Childe Harold's Pilgrimage" is a long narrative poem in four parts written by Lord Byron. The poem was published between 1812 and 1818. The poem contains elements thought to be autobiographical, as Byron generated some of the storyline from experience gained during his travels through Portugal, the Mediterranean and Aegean Sea between 1809 and 1811.

Throughout the poem, Byron, in character of Childe Harold, regretted his wasted early youth, hence re-evaluating his life choices and re-designing himself through going on the pilgrimage, during which he lamented various historical events including the Iberian Peninsular War.

Despite Byron's initial hesitation at having the first two cantos of the poem published because he felt it revealed too much of himself, it was published, at the urging of friends, by John Murray in 1812, and brought both the poem and its author to immediate and unexpected public attention.

Published on March 3, 1812, the first run of 500 quarto copies sold out in three days. There were ten editions of the work within three years. Byron was deeming the work "my best" in 1817, a year before adding a fourth canto.

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