Factual error: The film has the Earps arriving in Tombstone whilst on a cattle drive, however, the Earps were never cowboys. They were lawmen and gamblers. It also depicts Virgil being killed, who in fact lived until October 1905.
Factual error: The movie portrays Doc Holliday as a medical doctor when the townspeople expect him to operate on the wounded Chihuahua. Doc Holliday was not a MD, his title as "Doc" was for his DDS degree. He was a dentist.