"Song of Myself" is the final title Walt Whitman gave to his long, changing, remarkably fluid poem that he originally published as "Leaves of Grass" in the first edition of Leaves of Grass (1855).

It was renamed "Poem of Walt Whitman, an American" in the 1856 edition and was called simply "Walt Whitman" in the editions of 1860, 1867, and 1871. Only in the final edition of Leaves of Grass in 1881 did the poem become "Song of Myself." Not just the title but many other features of the poem changed over the years: Whitman radically altered the punctuation, added some sections and deleted others, tinkered with many individual lines, and divided up the poem in very different ways. In its original form, the poem had unnumbered stanzas that varied from a single line to over eighty lines; by 1860 Whitman had numbered these stanzas from 1 to 372; and by 1867 he had further divided the poem into fifty-two numbered sections,...