William Carlos Williams (September 17, 1883 – March 4, 1963) was a poet closely associated with modernism and imagism. His work has a great affinity with painting, in which he had a lifelong interest.

In his modernist epic collage of place entitled Paterson (published between 1946 and 1958), an account of the history, people, and essence of Paterson, New Jersey, Williams wrote his own modern epic poem, focusing on "the local" on a wider scale than he had previously attempted. He also examined the role of the poet in American society and famously summarized his poetic method in the phrase "No ideas but in things" (found in his poem "A Sort of a Song" and repeated again and again in Paterson).

In his later years, Williams mentored and influenced many younger poets. He had an especially significant influence on many of the American literary movements of the 1950s, including the Beat movement, the San Francisco Renaissance, the Black Mountain school, and the New York School.

One of Williams's most dynamic relationships as a mentor was with fellow New Jersey poet Allen Ginsberg. Williams included several of Ginsberg's letters in Paterson, stating that one of them helped inspire the fifth section of that work. Williams also wrote the introduction to Ginsberg's important first book, Howl and Other Poems, in 1956.