The Skeleton Canyon massacres refer to two separate lethal attacks on Mexican citizens that took place in 1879 and 1881 in Skeleton Canyon, located in the Peloncillo Mountains of Hidalgo County, on the border between present-day Arizona and New Mexico. The canyon links the Animas Valley of New Mexico with the San Simon Valley of Arizona.
The first attack occurred in July 1879. Cattle rustlers had assaulted a rancho in northern Sonora, Mexico, killing several inhabitants. Survivors reported the attack to Commandant Francisco Neri, who dispatched a detachment of Mexican Rurales, including Captain Alfredo Carrillo, to pursue the attackers. The Rurales crossed the international border into Arizona, and as they entered Skeleton Canyon, they came under fire. Of the large group that had crossed, only three Rurales survived. The Mexican government did not take further action but lodged a protest over the killings with U.S. President Chester Arthur, while acknowledging that its own policemen had crossed into Arizona territory. Johnny Ringo, associated with an outlaw group known as the Cochise County Cowboys — cattle rustlers and bandits operating in the region — claimed to have been present at the ambush. Ringo stated that other participants included "Old Man" Clanton, brothers Ike and Billy Clanton, "Curly Bill" Brocius, Florentino Cruz, and brothers Frank and Tom McLaury.
A second, related attack occurred in July 1881. Curly Bill Brocius learned that a group of Mexicans carrying silver were traveling through Skeleton Canyon toward Arizona. Brocius and roughly twenty other men, including Johnny Ringo and Jim Crane, ambushed the group, killing four people and stealing approximately $4,000 in bullion along with livestock. Two months after surviving victims reported this attack, Commandant Neri again sent Rurales, once more led by Captain Carrillo, across the border. This time the Rurales successfully ambushed the outlaw group, killing five men, including Old Man Clanton and Jim Crane, in a confrontation that became known as the Guadalupe Canyon Massacre.
The events have since been referenced in popular culture, including a 1958 episode of the television series Tombstone Territory depicting the 1881 attack, and a 1961 episode of The Life and Legend of Wyatt Earp titled "Requiem for Old Man Clanton," which references the Skeleton Canyon killings leading into the Guadalupe Canyon events.