Morley's father was a mathematician and his mother a musician and poet. They were both immigrants from England. The young Morley studied at Haverford College (B.A., 1910) and was a Rhodes scholar at New College, Oxford (1910–13). Over the years he found success in several fields. He gained popularity with his literary columns in the New York Evening Post (1920–24) and the Saturday Review of Literature (1924–41) and from collections of essays and columns such as Shandygaff (1918). His first novel was the popular Parnassus on Wheels (1917), about an itinerant bookseller's adventures and romance. His other novels include the innovative The Trojan Horse (1937), a combination of prose, verse, and dramatic dialogue that satirized human devotion to luxury, and the sentimental best-seller Kitty Foyle (1939), about an office girl and a socialite youth. The Old Mandarin (1947) is a collection of witty free verse. Morley also edited Bartlett's Familiar Quotations (1937, 1948).