Western fiction is a genre of literature set in the American Old West frontier and typically set from the late eighteenth to the late nineteenth century. Well-known writers of Western fiction include Zane Grey from the early 20th century and Louis L'Amour from the mid-20th century. The genre peaked around the early 1960s, largely due to the popularity of televised Westerns such as Bonanza. Readership began to drop off in the mid- to late 1970s and reached a new low in the 2000s. Most bookstores, outside a few west American states, only carry a small number of Western fiction books.

The predecessor of the Western in American literature emerged early with tales of the frontier. The most famous of the early 19th-century frontier novels were James Fenimore Cooper's five novels comprising the Leatherstocking Tales. Cooper's novels were largely set in what was at the time the American frontier: the Appalachian Mountains and areas west of there. As did his novel The Prairie (1824), most later Westerns would typically take place west of the Mississippi River.

The notable writer Washington Irving was inspired by Cooper and wrote tales of the American frontier beginning with A Tour on the Prairies which related his recent travels on the frontier. In 1834, he was approached by fur magnate John Jacob Astor, who convinced him to write a history of his fur trading colony in Astoria, Oregon. Irving made quick work of Astor's project, shipping the fawning biographical account Astoria in February 1836.

The Western as a specialized genre got its start in the "penny dreadfuls" and later the "dime novels". Published in June 1860, Malaeska; the Indian Wife of the White Hunter is considered the first dime novel. These cheaply made books were hugely successful and capitalized on the many stories that were being told about the mountain men, outlaws, settlers, and lawmen who were taming the western frontier. Many of these novels were fictionalized stories based on actual people, such as Billy the Kid, Buffalo Bill, Wyatt Earp (who was still alive at the time), Wild Bill Hickok, and Jesse James.

By 1900, the new medium of pulp magazines helped to relate these adventures to easterners. Meanwhile, non-American authors, like the German Karl May, picked up the genre, went to full novel length, and made it hugely popular and successful in continental Europe from about 1880 on, though they were generally dismissed as trivial by the literary critics of the day. One of the most famous pulp works of the era was Johnston McCulley's first Zorro novel, The Curse of Capistrano (1919).

Popularity grew with the publication of Owen Wister's novel The Virginian (1902) and especially Zane Grey's Riders of the Purple Sage (1912). The first Hopalong Cassidy stories by Clarence Mulford appeared in 1904, both as dime novels and in pulp magazines. When pulp magazines exploded in popularity in the 1920s, Western fiction greatly benefited (as did the author Max Brand, who excelled at the Western short story). Pulp magazines that specialised in Westerns include Cowboy Stories, Ranch Romances, Star Western, West, and Western Story Magazine. The simultaneous popularity of Western movies in the 1920s also helped the genre.

In the 1940s several seminal Westerns were published, including The Ox-Bow Incident (1940) by Walter van Tilburg Clark, The Big Sky (1947) and The Way West (1949) by A.B. Guthrie Jr., and Shane (1949) by Jack Schaefer. Many other Western authors gained readership in the 1950s, such as Ray Hogan, Louis L'Amour, and Luke Short.

The genre peaked around the early 1960s, largely due to the tremendous number of Westerns on television. The burnout of the American public on television Westerns in the late 1960s seemed to have an effect on the literature as well, and interest in Western literature began to wane.^{[citation needed]} In 1968 Charles Portis published True Grit, which became the most successful work of the era.