Crabb Massacre The Crabb Massacre was the culmination of the eight day Battle of Caborca . It was fought between Mexico and their O ' odham allies against American forces in April 1857 . Due to the outbreak of the Reform War in Mexico , the rebel Ygnacio Pesqueira invited the American politician Henry A . Crabb to colonize the northern frontier region in the state of Sonora , on the basis that the colonists would help Pesqueira fight in the civil war and against the Apache . However , when Crabb arrived in Mexico , his command was attacked and ultimately defeated . Some fifty survivors of the battle , out of about eighty - five men , were executed by the Mexicans . Background . The Reform War was a religious civil war , one of many between Mexico ' s rival conservative and liberal factions . Ygnacio Pesqueira fought for the liberals in Sonora , against the state soldiers of the conservative Governor Manuel María Gándara . General Crabb was a former state senator from California , as well as a former United States Army officer , but his journey to Mexico in 1857 , known as the Crabb Expedition , was of a private nature and did not involve the American government or the military . It was in the fall of 1856 , after Crabb lost an election to decide the next senator of California , when he came into contact with Pesqueira through his Mexican wife . Crabb accepted Pesqueira ' s offer who authorized the general to bring 1 , 000 colonists . But by the time the expedition left for Mexico , the general had recruited only about 100 men . Other volunteers organized to follow Crabb into Sonora either abandoned the march or were attacked by the Mexicans . Starting out from San Diego in January 1857 , the expedition went to the Lower Colorado River and then entered New Mexico Territory , now Arizona , and headed directly for the Gila River where they gathered livestock for several weeks . The location of the camp is now known as the Filibusters Camp . In March they went south for the Tucson area to recruit more men . From Tucson the expedition continued further south to Altar , where they would meet with Pesqueira and his rebels . By the time Crabb reached Sonora , the rebels had already defeated Gándara ' s troops and forced him into exile . Gándara later sought refuge in Tucson . Conflict . The Crabb expedition first made contact with the rebels at Caborca , having diverged a bit from Altar , their original destination . Now that he no longer needed the American colonists , Pesqueira was criticised by his followers for accepting to use Americans in the war . Because of this , the rebels decided to destroy the expedition . Crabb sent the prefect of Altar a message saying that he had come in peace but the message was either ignored or failed to arrive in time to influence the situation . At Caborca the Americans became involved in a skirmish which took eight days to finish according to George N . Cardwell who wrote an account of the affair in a letter to his brother J . W . Cardwell . Massacre . George Cardwell , an associate of some of the expedition ' s members , wrote that at the conclusion of the battle , in which twenty - five Americans were killed , the remaining fifty - eight were separated into groups of ten and executed by firing squad . Crabb ' s men took up positions inside an adobe building but it was later set on fire by an O ' odham warrior , forcing their surrender . Cardwell ' s letter says that eighty - four Americans were killed in all , including General Crabb , though other accounts say only forty - one Americans were killed in the massacre itself , not including those who died during the fighting . In Cardwell ' s letter , he includes a list of fifty - five of the Americans who died and says that among them were California ' s most respectable citizens . Cardwell wrote that the Mexicans lost 200 men out of about 1 , 500 . This number included dozens of O ' odham . The Mexican commander , Hilario Gabilonda , who had received instructions from Pesqueira to shoot the prisoners , refused to carry out his orders and left with a fourteen - year - old American boy named Evans . Evans was raised by Gabilonda and later became a Mexican customs inspector at the international border with the United States . General Crabb was allowed to write a letter to his wife before being executed by a firing squad of 100 men , after which his head was cut off and preserved in a jar . The letter was given to one of two men who left the expedition before it crossed the international border between Arizona and Sonora . At the time the Crabb Expedition was regarded by many Mexicans and Americans as being an outfit of filibuster s , organized to conquer Mexican territory , but it was sanctioned by the rebel government in Mexico , which would eventually win the Reform War in 1861 . Cardwell himself wrote that " " Mr . Crabb left here about January last , ostensibly for the purpose of mining in the Gadsden purchase , and settling there ; but really intending to conquer Sonora , and in process of time add it to the slave states . " " Aftermath . The conflict was not over , however . Cardwell writes that " " some days " " after the Caborca affair , a group of twenty Mexicans crossed the border , from San Juan , into Arizona and captured four men of Crabb ' s party who were resting in a general store due to illness . These four were executed . Shortly thereafter , twenty of Crabb ' s volunteers launched an expedition to relieve General Crabb . Led by Major R . N . Wood and Captain Granville Henderson Oury of Tucson , the rescue party was on the Mexican side of the border when about 200 Mexicans attacked them near the location where the four sickly men had been captured . After " " severe fighting " " , these twenty recruits successfully made it back across the border . A squad of sixteen other recruits was not so fortunate , and after crossing the border were intercepted by the same 200 men who had encountered Major Wood and Captain Oury . These men surrendered without a fight but were executed like the others . Of the Americans who participated in the Battle of Caborca , only one or two men survived , included the fourteen - year - old Evans . Accounts differ as to the existence of a second survivor . In California and New Mexico Territory , news of the massacre created a clamor for revenge against the Mexicans but the incident was eventually put aside and forgotten . Some time later , Gabilonda , who had refused to kill the American colonists , was nearly lynched in Tucson by an angry mob , but survived apparently because of his innocence .