George Peppin was born at Mountsville, Vermont, October 1841. He enlisted in the 5th Infantry California Volunteers in 1861. After the American Civil War he moved to Lincoln County where he worked as a stone mason.
In 1874 James Dolan and Lawrence Murphy became business partners and established the Murphy & Dolan mercantile and banking operation. In 1876 Alexander McSween and John Tunstall set up a rival business. The activities of these two men upset Dolan and Murphy. Dolan attempted to goad Tunstall into a gunfight. Tunstall refused to use violence himself but he did recruit Billy the Kid to help him in his business dispute. On 18th February, 1878, Tunstall was killed by William Morton, Jesse Evans and Tom Hill. This incident started what became known as the Lincoln County War.
Billy the Kid was deeply affected by this murder and claimed that Tunstall "was the only man that ever treated me like I was a free-born and white." Apparently at Tunstall's funeral Billy the Kid swore: "I'll get every son-of-a-bitch who helped kill John if it's the last thing I do."
Billy the Kid joined the Regulators, a group that supported Alexander McSween. It was claimed that John Tunstall had been murdered on the orders of James Dolan and Lawrence Murphy. Rumours began to circulate that Dolan had offered $1,000 for anyone willing to murder Alexander McSween. Over the next few months the Regulators killed Sheriff William Brady, George Hindman, William Morton, Buckshot Roberts and others who they claimed they had been involved in the killing of Tunstall.
In April, 1878, James Dolan arranged for Peppin to be appointed as a replacement for Sheriff William Brady. On 19th July, 1878, Alexander McSween and his supporters, including Billy the Kid, were besieged by Sheriff Peppin and a group of his men. McSween's house was set on fire and several people were shot dead as they came out of the house. This included McSween.
Peppin was indicted by the grand jury for setting fire to the McSween home. The charge was later dropped and no one was convicted for the murder of Alexander McSween.
After leaving office Peppin worked as a butcher at Fort Stanton. Later he was employed by Pat Coghlan in his meat business.
George Peppin died in Lincoln County on 14th September, 1904.