The Western is a fiction genre seen in film, television, radio, literature, painting and other visual arts. Westerns are devoted to telling stories set primarily in the later half of the 19th century in what became the Western United States (known as the American Old West or Wild West), but also in Western Canada, Mexico (The Wild Bunch, Vera Cruz), Alaska (The Far Country, North to Alaska) and even Australia (Quigley Down Under, The Proposition). Some Westerns are set as early as the Battle of the Alamo in 1836 but most are set between the end of the American Civil War and the massacre at Wounded Knee in 1890, though there are several "late Westerns" (e.g., The Wild Bunch and 100 Rifles) set as late as the Mexican Revolution in 1913. There are also a number of films about Western-type characters in contemporary settings where they don't fit in, such as Junior Bonner set in the 1970s, and Down in the Valley and The Three Burials of Melquiades Estrada in the 21st century.

Westerns often portray how primitive and obsolete ways of life confronted modern technological or social changes. This may be depicted by showing conflict between natives and settlers or U.S. Cavalry or between sheep and cattle farmers, or by showing ranchers being threatened by the onset of the Industrial Revolution. American Westerns of the 1940s and 1950s emphasize the values of honor and sacrifice. Westerns from the 1960s and 1970s often have more pessimistic view, glorifying a rebellious anti-hero and highlighting the cynicism, brutality and inequality of the American West. Despite being tightly associated with a specific time and place in American history, these themes have allowed Westerns to be produced and enjoyed across the world.