The poet was a contributor back in the day. Though they got off to a rocky start:
Sometime in 1912, before Robert Frost made his famous leap to "live under thatch" in England, where he would become known as a poet, he sent some of his poems to Ellery Sedgwick, the editor of The Atlantic Monthly, and in due course received a personal reply that
read, "We are sorry that we have no place in The Atlantic Monthly for your vigorous verse." Frost's submission included some of his finest early poems "Reluctance," for example.
Sedgwick's ambiguous snub rankled in Frost's memory. During the two and a half years he lived in England his first two books of poetry, A Boy's Will (1913) and North of Boston (1914), were published there, though not yet in the United States. Thanks partly to Ezra Pound, Amy Lowell, and Harriet Monroe's Poetry magazine, Frost's poems were hailed in advance of U.S. publication as representing a new American voice. In February, 1915, North of Boston was published in New York, just as the Frost family set foot back in the United States.
Response to this new book of poems about New England was nearly immediate, and Frost was quickly in demand for public appearances. On May 5, 1915, he came to Boston from his new home in Franconia, New Hampshire, to be heard at Tufts University, where he read three of his as yet unpublished poems: "Birches," "The Road Not Taken," and "The Sound of Trees." The day after his Tufts appearance, he called on Ellery Sedgwick at the Atlantic offices, which the magazine shared with Houghton Mifflin Company at 4 Park Street. Sedgwick had just received a letter from the noted English editor and critic Edward Garnett (also the discoverer of Joseph Conrad and D. H. Lawrence), in which Garnett wrote that "since Whitman's death, no American poet has appeared, of so unique a quality, as Mr. Frost." It's not surprising that Sedgwick received Frost with a warm welcome and began by asking if Frost had any new poems for The Atlantic.
Listen to three of his published poems here (and a rejected one here). Read Edward Garnett's 1915 essay "A New American Poet" here. Check out Mark Van Doren's 1951 cover story here.