Short answers, pulled from the story.
The 13th Warrior is based on Michael Crichton's novel Eaters of the Dead published in 1976. This book merged the ancient Anglo-Saxon epic poem Beowulf with the travel journal of Ahmad ibn Fadlan from the tenth century.
Principal photography began in the summer of 1997 under director John McTiernan. Michael Crichton later took over directing duties after test audiences reacted poorly to the initial cut.
The film grossed only $61 million worldwide against its massive production costs. Financial losses ranged between $70 million and $130 million depending on accounting methods.
Omar Sharif retired from acting after this experience due to disappointment with the script. He stated bad pictures were humiliating and terrifying to perform.
Roger Ebert awarded the film one and a half stars out of four. He criticized the pacing and lack of emotional connection to characters.