Harry Alverson Franck was an American travel writer during the first half of the 20th century.

Hiram Gilmore "Harry" Bates III was an American science fiction editor and writer. His short story "Farewell to the Master" (1940) was the basis of the well-known science fiction movie The Day the Earth Stood Still (1951).

Charles Austin Fosdick, better known by his nom de plume Harry Castlemon, was a prolific writer of juvenile stories and novels, intended mainly for boys. He was born in Randolph, New York, and received a high school diploma from Central High School in Buffalo, New York. He served in the Union Navy from 1862 to 1865, during the American Civil War, acting as the receiver and superintendent of coal for the Mississippi River Squadron. Fosdick had begun to write as a teenager, and drew on his experiences serving in the Navy in such early novels as Frank on a Gunboat (1864) and Frank on the Lower Mississippi (1867). He soon became the most-read author for boys in the post-Civil War era, the golden age of children's literature.

Harry Collingwood was the pseudonym of William Joseph Cosens Lancaster, a British civil engineer and novelist who wrote over 40 boys' adventure books, almost all of them in a nautical setting.

Harry Emerson Fosdick was an American pastor. Fosdick became a central figure in the Fundamentalist–Modernist controversy within American Protestantism in the 1920s and 1930s and was one of the most prominent liberal ministers of the early 20th century. Although a Baptist, he was called to serve as pastor, in New York City, at First Presbyterian Church in Manhattan's West Village, and then at the historic, inter-denominational Riverside Church in Morningside Heights, Manhattan.

Harry Max Harrison was an American science fiction author, known mostly for his character The Stainless Steel Rat and for his novel Make Room! Make Room! (1966). The latter was the rough basis for the motion picture Soylent Green (1973). Long resident in both Ireland and the United Kingdom, Harrison was involved in the foundation of the Irish Science Fiction Association, and was, with Brian Aldiss, co-president of the Birmingham Science Fiction Group.

Harry James Smith was an American playwright and novelist. His best known plays include A Tailor-Made Man, first produced in 1917 and adapted into films of the same name in 1922 and 1931. His 1913 play Blackbirds was also adapted into films. Educated at Williams College and Harvard University, he also studied biology, taught briefly at Oberlin University and was an editor at The Atlantic Monthly before turning to writing full-time. He was killed in a traffic collision in British Columbia while collecting peat moss for its use in surgical dressings.

Harry Hibbard Kemp was an American poet and prose writer of the twentieth century. He was known as the "Vagabond Poet", the "Villon of America", the "Hobo Poet", or the "Tramp Poet", and was a well-known popular literary figure of his era, the "hero of adolescent Americans."

Harry Leon Wilson was an American novelist and dramatist best known for his novels Ruggles of Red Gap and Merton of the Movies. Another of his works, Bunker Bean, helped popularize the term "flapper".

Harry Quilter, was an English art critic, writer and artist.