Twelve Union
cavalry troopers and one
scout (reported to be
mountain man Pauline Weaver but in reality Arizona City (Now Yuma, AZ) resident John W. Jones), commanded by
Lieutenant James Barrett of the 1st California Cavalry, were conducting a sweep of the Picacho Peak area, looking for Confederates reported to be nearby. The Arizona Confederates were commanded by
Sergeant Henry Holmes. Barrett was under orders not to engage them, but to wait for the main column to come up. However, "Lt. Barrett acting alone rather than in concert, surprised the Rebels and should have captured them without firing a shot, if the thing had been conducted properly." Instead, in the midafternoon the lieutenant "led his men into the thicket single file without dismounting them. The first fire from the enemy emptied four saddles, when the enemy retired farther into the dense thicket and had time to reload. ... Barrett followed them, calling on his men to follow him." Three of the Confederates surrendered. Barrett secured one of the prisoners and had just remounted his horse when a bullet struck him in the neck, killing him. Fierce and confused fighting continued among the mesquite and arroyos for 90 minutes, with two more Union fatalities and three troopers wounded. Exhausted and leaderless, the Californians broke off the fight and the
Arizona Rangers, minus three who surrendered, mounted and carried warning of the approaching Union army to Tucson. Barrett's disobedience of orders had cost him his life and lost any chance of a Union surprise attack on Tucson. The Union troops retreated to the Pima Indian Villages and hastily built a
fort named in Barrett's honor at
White's Mill, waiting to gather resources to continue the advance. However, with no Confederate reinforcements available, Captain
Sherod Hunter and his men withdrew as soon as the column again advanced. The
Union troops entered Tucson without any opposition. The bodies of the two Union enlisted men killed at Picacho (George Johnson and William S Leonard) were later removed to the National Cemetery at the
Presidio of San Francisco in
San Francisco, California. However, Lieutenant Barrett's grave, reportedly buried near the present railroad tracks, remains undisturbed and unmarked as the site was lost. Union reports claimed that two Confederates were wounded in the fight, but Captain Hunter in his official report listed no Confederate casualties other than the three men captured. One of the rebels named John Hill was recognized by a Private Frank Clark, as they were both from
Napa. ==Aftermath==