The 13th Warrior is a 1999 American historical fiction action film based on Michael Crichton's 1976 novel Eaters of the Dead, which is a loose adaptation of the tale of Beowulf combined with Ahmad ibn Fadlan's historical account of the Volga Vikings.

It stars Antonio Banderas as Ahmad ibn Fadlan, as well as Diane Venora and Omar Sharif. It was directed by John McTiernan; Crichton directed some uncredited reshoots. The film was produced by McTiernan, Crichton, and Ned Dowd, with Andrew G. Vajna, James Biggam and Ethan Dubrow as executive producers.

Production and marketing costs reportedly ranged from $100–$160 million, but it grossed $61 million at the box office worldwide, becoming the biggest box office bomb of 1999, with losses of up to $129 million. Despite its critical and box office failure, the film has since cultivated a devoted cult following, and is credited with pioneering a Muslim hero in Hollywood blockbusters.