The Prelude, autobiographical epic poem in blank verse by William Wordsworth, published posthumously in 1850. Originally planned as an introduction to another work, the poem is organized into 14 sections, or books. Wordsworth first began work on the poem in about 1798. It would absorb him intermittently for the next 40 years, as can be seen in the fact that the poem went through four distinct manuscript versions (1798–99, 1805–06, 1818–20, and 1832–39). The Prelude treats as its central subject the narrator’s development as a poet, the forces that shaped his imaginative powers, and his spiritual crisis and recovery.