Alexander McSween was a prominent figure during the Lincoln County War of the Old West, and a central character, alongside John Tunstall, in opposing businessmen and gunmen Lawrence Murphy and James Dolan.

John Henry Tunstall was an English-born rancher and merchant in Lincoln County, New Mexico, United States. He competed with the Irish Catholic merchants, lawmen, and politicians who ran the town of Lincoln and the county. Tunstall, a member of the Republican Party, hoped to unseat the Irish and make a fortune as the county's new boss. He was the first man killed in the Lincoln County War, an economic and political conflict that resulted in armed warfare between rival gangs of cowboys and the ranchers, lawmen, and politicians who issued the orders.