Doc Holliday was born on the East Coast of America to a wealthy family. They moved up an down the coast, never staying in one place for too long; his father had many business ventures along the coast, and he liked to keep his hands in all of them.
Not being satisfied with his life (despite the privilege he had been born to), Doc began doing everything he could to differentiate himself from the rest of his family. He began smoking and drinking when he was very young, and it was not long before he started learning how to shoot. He found himself a teacher who had been born and raised on the frontier, getting lessons whenever he could get himself away from his family (often making up some sort of excuse to meet up with his teacher).
It was not long before he became an even better shooter than his teacher, and he would challenge gentleman for money to see who the better shooter was. Many of these gentlemen would not take him seriously, thinking that they would easily beat him because of his age. They quickly learned that they had made a colossal mistake, and his reputation as a sharpshooter spread.
When his family heard about what he had been doing, his parents were furious. They demanded that he stop competing with people, and at first (to keep the peace) he pretended to agree to stop. What they did not know was that as soon as he thought they were not being as watchful of his actions and whereabouts, he began sneaking out again. The difference this time was that he purposefully looked for people who were a challenge to him, and this time he lost more times than he had before.
Still, he had retained his reputation as an amazing shooter.
The word got back to his family again, and rather than suffer the embarrassment that his actions would have caused them, his father kicked him out of the family home, saying that he was no longer welcome back.
He left in anger, taking only his guns and the clothes that he was wearing. He went back to challenging men he was sure he could beat, winning enough money to make sure he was able to eat. Saving enough of his money to book passage on a train, he started making his way to the frontier, where the people had not heard of his skill.
When he arrived, he began challenging people again, making as much money as he could while the money was good. He spent as little as possible, and eventually, he had enough to buy his own saloon. By the time that he bought the[KO1] saloon, most of the people in the area had heard about him, and those who were willing to accept his challenges had started running out.
Still wanting something of a challenge, he turned his attention to poker; he found this more of a challenge than shooting, not winning nearly as many times as he would have liked (but he still won enough, and he had the earnings from his salon and the girls that worked there).
It was during one of the poker games that he met Wyatt Earp, who he hated from the moment they laid eyes on each other. But when a fight broke out between the Earp brothers and the cowboys, Doc took the side of the Earp brothers.
The fight started during a poker game in his saloon, and it was discovered that the cowboys had been trying to cheat. This offended him (as it meant the loss of money for him), and he joined them in their confrontation with the cowboys, where he was injured.
He recovered slowly, because he joined Wyatt in his quest for vengeance against the cowboys (who had killed one of his brothers during the shootout).
Along the way, Dob became sick with a mysterious disease that the doctors in the West were unable to identify. He stayed alive just long enough to help Wyatt find all of the cowboys who had been responsible for his brother’s death. Not long after, he was admitted into a hospital that was run by nuns, and he died not long after (passing away in his sleep).