John Horton Slaughter, also known as Texas John Slaughter, was an American lawman, cowboy, poker player and rancher in the Southwestern United States during the late 19th and early 20th centuries. After serving in the Confederate States Army during the American Civil War, Slaughter earned a reputation fighting hostile Indians and Mexican and American outlaws in the Arizona and New Mexico territories. In the latter half of his life, he lived at the San Bernardino Ranch, which is today a well-preserved National Historic Landmark in Cochise County in far southeastern Arizona. In 1964, he was inducted into the Hall of Great Westerners of the National Cowboy & Western Heritage Museum.

The Apache Campaign of 1896 was the final United States Army operation against Apaches who were raiding and not living in a reservation. It began in April after Apache raiders killed three white American settlers in the Arizona Territory. The Apaches were pursued by the army, which caught up with them in the Four Corners region of Arizona, New Mexico, Sonora and Chihuahua. There were only two important encounters during the campaign and, because both of them occurred in the remote Four Corners region, it is unknown if they took place on American or Mexican soil.