Meredith was born in New York City to William Morris Meredith Sr. and Nelley Keyser. He attended Lenox School in Massachusetts, graduating in 1936. He began writing while a college student at Princeton University. He graduated magna cum laude from Princeton in 1940, having written a senior thesis on Robert Frost. His first volume of poetry, Love Letter from an Impossible Land, appeared in 1944. Archibald MacLeish selected it for publication as part of the Yale Series of Younger Poets Competition.

Meredith worked briefly for the New York Times as a copy boy and reporter before joining the United States Army Air Force in 1941. The next year, he transferred to the United States Navy as a carrier pilot. He served in the Aleutian Islands and Pacific Theater and reached the rank of lieutenant. He continued his service in the United States Navy Reserve until 1952, when he reenlisted to serve in the Korean War. He ultimately attained the rank of lieutenant commander and was awarded two Air Medals.

From 1946 to 1950, Meredith had several teaching appointments at Princeton University: Instructor in English, Woodrow Wilson Fellow in Writing, and Resident Fellow in Creative Writing. This was followed by an appointment as associate professor at the University of Hawaii (1950–51). After the Korean War he was hired as an associate professor of English at Connecticut College, where he taught until 1983. Meredith was promoted to professor in 1965. He settled on a farm in Uncasville, where he continued to write poetry and developed his talents as an arborist, planting and nurturing rare trees on the banks of the Thames. During this period, he also taught for several years in the summer graduate program at Middlebury College’s Bread Loaf School of English. He was also an instructor at the Bread Loaf Writers’ Conference from 1964 to 1971.

From 1964 to 1987, Meredith served as Chancellor of the Academy of American Poets. From 1978 to 1980, he was Consultant in Poetry to the Library of Congress, the position which in 1985 became the Poet Laureate Consultant in Poetry to the Library of Congress. He has the distinction of being the first gay poet to receive this honor.

In 1983, Meredith suffered a stroke and was immobilized for two years. The stroke caused expressive aphasia, which affected his ability to produce language. Meredith ended his teaching career and could not write poetry during this period. He regained many of his language skills after intensive therapy and traveling to Britain for treatment.

In 1988, Meredith was awarded the Pulitzer Prize for Poetry and a Los Angeles Times Book Award for Partial Accounts: New and Selected Poems. In 1997, he won the National Book Award for Poetry for Effort at Speech. Meredith also received a Guggenheim Foundation fellowship, the Harriet Monroe Memorial Prize, the Carl Sandburg Award, and the International Vaptsarov Prize in Poetry.

Connecticut College acquired the papers in 1994. They are in the Special Collections department of the Charles E. Shain Library. One may consult the collection by arrangement with the Special Collections Librarian. The library also has a virtually complete collection of Meredith’s published work, including many of the anthologies and issues of literary journals in which individual poems were published or reprinted. The book collection also includes presentation copies of Robert Frost’s poetry that Frost gave Meredith, several with inscriptions and holograph poems.

A longtime admirer of W. B. Yeats, Meredith fulfilled his ambition to visit Yeats’s spiritual homeplace of Sligo, Ireland, in 2006. While there he also attended the Yeats International Summer School, which attracts many academics and admirers of Yeats to Sligo every summer.

Meredith died in New London, Connecticut, near his home in Montville, where he lived with his partner of 36 years, the poet and fiction writer Richard Harteis. A film about his life, Marathon, premiered on November 19, 2008, in Mystic, Connecticut.