The outlaw biker film is a film genre that portrays its characters as motorcycle riding rebels. The characters are usually members of an outlaw motorcycle club.
Outlaw biker clubs formed in the late 1940s on the West Coast after the end of World War II. Their culture was first popularized in the Marlon Brando film The Wild One (1953), which tells a story based very loosely on actual events. The film's success was followed by a string of low-budget exploitation films aimed at a teenage audience such as Motorcycle Gang (1957) and The Hot Angel (1958). But the genre really took off in the mid-1960s, after the Hell's Angels gang became prominent in the media, in particular, after Hunter S. Thompson's book Hell's Angels: The Strange and Terrible Saga of the Outlaw Motorcycle Gangs (1966) was published.
In 1965, director Russ Meyer made Motorpsycho (aka Motor Psycho), an obscure film about an evil motorcycle gang led by a disturbed Vietnam War veteran. In 1966, American International Pictures (AIP) released The Wild Angels with Peter Fonda, Bruce Dern, and Nancy Sinatra. This film, aimed at the teenage drive-in crowd, was a surprise hit and a new exploitation film subgenre was born. AIP dominated the market and quickly released a semi-sequel Devil's Angels starring actor-director John Cassavetes and The Glory Stompers with Dennis Hopper in 1967.