Walker is a 1987 American-Mexican historical, hybrid/weird western film directed by Alex Cox and starring Ed Harris, Richard Masur, René Auberjonois, Peter Boyle, Miguel Sandoval and Marlee Matlin. The film is based on the life story of William Walker, the American filibuster who invaded and made himself president of Nicaragua. It was written by Rudy Wurlitzer and scored by Joe Strummer, who has a small role as a member of Walker's army.

Alexander B. H. Cox is an English film director, screenwriter, actor, non-fiction author and broadcaster. Cox experienced success early in his career with Repo Man and Sid and Nancy, but since the release and commercial failure of Walker, his career has moved towards independent films. Cox received a co-writer credit for the screenplay of Terry Gilliam's Fear and Loathing in Las Vegas (1998) for previous work on the script before it was rewritten by Gilliam.