This copy of a weekly magazine published at the beginning of the twentieth century shows how westerns were written about more than 100 years ago. Boy how things have changed. Dusty Richards once told me that the pioneers in western writing did all the hard work. They had to describe a land not seen by many Americans. A wild and rugged view of landscape and people that were often hard to explain to anyone who hadn't been west of the Mississippi. Imagine writing about a vast desert and expecting a city slicker back east to see it. It took a lot of skill to explain to readers where the hero's horse tread. Below is a short explanation I found that explains a little about western literature and its history.
The predecessor of the western in American literature emerged early with tales of the frontier. The most famous of the early nineteenth century frontier novels of the frontier were James Fenimore Cooper's, the five novels making up 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 1824 novel The Prairie most later westerns would typically take place west of the Mississippi River.
1850s-1900The 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: Buffalo Bill, Wild Bill Hickok, Jesse James, Wyatt Earp (who was still alive at the time) and Billy the Kid.
By 1900, the new medium of pulp magazines also 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.
1900s-1930sPopularity grew with the publication of Owen Wister's The Virginian in 1902 and especially Zane Grey's Riders of the Purple Sage in 1912. The first Hopalong Cassidy stories by Clarence l. 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 inclued Western Story Magazine, Star Western, West, Cowboy Stories and Ranch Romances.  The simultaneous popularity of Western movies in the 1920s also helped the genre.
1940s-1960sIn 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 Luke Short, Ray Hogan, and Louis L'Amour.
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.