James Ingram Merrill was born in New York City on March 3, 1926, the son of Charles Merrill, co-founder of the brokerage firm Merrill Lynch, and his second wife, Hellen Ingram. His parents were divorced in 1939.
Merrill grew up in Manhattan and Southampton, New York. He was already writing poems by the time he was eight years old and when he was 16, at Lawrenceville School, his father had a book of Merrill's juvenile poems privately printed under the title of Jim's Book.
Following Lawrenceville, Merrill went to Amherst College, where he met Robert Frost. His college studies were interrupted by military service in the US Army from 1944 to 1945. Another book, The Black Swan, was privately published in 1946, when Merrill was back at Amherst, where he graduated summa cum laude in 1947. His subject of his undergraduate thesis was metaphor in Proust.
After graduation, Merrill taught at Bard College for a year and then left for Europe for 2 ½ years, a time he described in his memoir A Different Person. His first publicly published book of poems was First Poems (Alfred A. Knopf) in 1951.
Merrill moved to Stonington in 1955 with his companion David Jackson. That same year his first play The Immortal Husband was produced and published in Playbook the following year. In 1956 he took a portion of his inheritance to establish the Ingram Merrill Foundation in New York City, which has awarded grants to hundreds of artists and writers. Merrill's first novel Seraglio was published by Knopf in 1957. In 1959 he and David Jackson took a house in Athens, Greece, where they spent part of each year until 1979. In 1960 The Bait, his second play, was published in Artist's Theater.
Merrill's second novel The (Diblos) Notebook, published in 1965, was a finalist for the National Book Award in Fiction and in 1966 his Nights and Days won the National Book Award in Poetry. This began a series of prizes for Merrill's writing, including the Bollingen Prize for Braving the Elements (1972), the Pulitzer Prize for Divine Comedies, (1976), a second National Book Award for Mirabell (1978), the National Book Critics Circle Award for the epic poem The Changing Light at Sandover (1982) and the first Bobbitt National Prize for Poetry awarded by the Library of Congress for The Inner Room (1988).
James Merrill served as Chancellor of the Academy of American Poets from 1979 until his death on February 6, 1995, of a heart attack while vacationing in Arizona. He was 68 years old. A Scattering of Salts was published by Alfred A. Knopf a month later.