Harry Weldon Kees (February 24, 1914 – disappeared July 18, 1955) was an American poet, librarian, painter, literary critic, novelist, playwright, jazz pianist, short story writer, and filmmaker. Despite his brief career, Kees is considered an important mid-twentieth-century poet of the Beat generation, and peer of John Berryman, Elizabeth Bishop, and Robert Lowell. His work has been immensely influential on subsequent generations of poets writing in English and other languages and his collected poems have been included in many anthologies. Harold Bloom lists the publication of Kees's first book The Last Man (1943) as an important event in the chronology of his textbook Modern American Poetry as well as a book worthy of his Western Canon.

Weldon Kees was born in Beatrice, Nebraska, to John Kees, a hardware manufacturer, and Sarah Green Kees, a schoolteacher. The Kees family was well-to-do, John being part owner of F.D. Kees Manufacturing Co., which patented and produced corn-husking hooks as well as innovative products such as a window defroster for automobiles and a moving lawn sprinkler that resembled a farm tractor. Weldon was a precocious child whose playmates included Robert Taylor and whose pastimes included producing his own magazines, giving puppet shows and even acting. He was treated like a small adult by his parents, whom he addressed by their first names.

Kees's worldview and writing were shaped by the Jazz Age and his early adulthood during the Great Depression. By the time he graduated from high school in 1931, he rejected entering the family business and, while at Doane College, decided to become a novelist. He transferred to the University of Missouri, which had a writing program, and then to the University of Nebraska, where he was mentored by the founding editor of the literary journal Prairie Schooner, Lowery C. Wimberley. By the time Kees graduated in 1935, he had already written and published short stories in that journal as well as other literary magazines such as Horizon and Rocky Mountain Review.

While working for the Federal Writers' Project in Lincoln, Nebraska, and after having suffered the rejection of several novels, Kees turned to writing poetry—and, for a time, engaged in union organizing and considered himself a communist. In 1937, Kees moved to Colorado to earn a degree in library science at the University of Denver, which included working as a librarian at the Denver Public Library.

He then became director of the Bibliographical Center of Research for the Rocky Mountain Region, which was used as a model for a national union catalog. That same year, he married Ann Swan.

In early 1941, Kees signed a provisional contract with Alfred A. Knopf for a novel, Fall Quarter, an academic black comedy about a young professor who battles the dreariness and banality of a staid Nebraskan college. Fall Quarter, part surreal, part social commentary, was rejected by Knopf in the days after the bombing of Pearl Harbor, the declaration of war having changed publishing contingencies for war books. A farce about a dystopic heartland would look unpatriotic on Knopf's 1942 list. From this point on, Kees turned from fiction to writing only poetry.

A pacifist, Kees left Denver for New York City, where he believed Selective Service psychiatrists were more likely to declare him unfit for military duty. He had also, during previous visits, made contacts with literary figures such as William Carlos Williams, Edmund Wilson and his then wife Mary McCarthy, Saul Bellow, Dwight Macdonald, Allen Tate, Lionel Trilling, and many others. It was during his first year in New York that he worked as a book and film critic for Time and as newsreel scriptwriter for Paramount News.

With his first book of poems, The Last Man (San Francisco: Colt Press, 1943), Kees quickly established his reputation and his poems began to appear regularly in The New Yorker (which published his first Robinson persona poems, which pathologize the urban man), Poetry, and The Partisan Review. By the time his second book appeared, The Fall of Magicians (New York: Reynal & Hitchcock, 1947), Kees had already been painting for more than a year and had befriended Abstract Expressionism artists, including Willem de Kooning, Robert Motherwell, Hans Hofmann, as well as the critic Clement Greenberg—whose column Kees took over at The Nation from 1948 to 1950.