On March 28, 1862, New Mexico (which then included the area now known as Arizona) played host to an often overlooked Civil War conflict; the Battle of Glorietta Pass. The Confederates involved in the battle hailed primarily from Texas, whereas the Union troops were based in Colorado.
Formed in 1862, the Colorado unit came together through the efforts of Territorial Governor John Evans and was composed of Colorado First Volunteers and Second Infantry; recruited to protect the Colorado Territory from Confederates and hostile Native Americans. The commanding officer of this group, Colonel John Chivington, would go on to become infamous in the Sand Creek Massacre.
Embarking on a bold plan to conquer Nevada and California, the Confederates hoped to acquire funds for their cash-strapped treasury by gaining access to gold and other mineral resources in Western mines.
Under the command of Brigadier General Henry H. Sibley, the Confederates left San Antonio and moved through southern New Mexico, with their goal to occupy the Santa Fe Trail as far north as Colorado; in addition to opening a line of communication with California. After capturing the towns of Messilla and Tucson, General Sibley headed north, accompanied by 3,000 troops, in an effort to capture Fort Craig.
As Sibley’s troops approached Fort Craig, they encountered Colonel Edward Canby’s Union troops during the Battle of Valverde on February 21st. The conquered Yankees took refuge at Fort Craig as the Confederates pressed forward towards the Pecos River; leaving a portion of their troops behind to occupy Santa Fe and Albuquerque. Located on the opposite side of the Sangre de Cristo Mountains, Fort Union was their next target.
Advancing with between 200-300 Texans, Major Charles L. Pyron crossed over the Glorieta Pass on the southern end of the Sangre de Cristo Mountains. Capture of the pass would provide General Sibley the opportunity to advance on and capture Fort Union, a prize target along the Santa Fe Trail.
When Pyron’s troops made camp at Apache Canyon, they came under attack by Yankee soldiers led by Major Chivington. In the process of assaulting Pyron’s troops, Chivington’s soldiers were initially beaten back by the Confederates. Splitting his force in two, Chivington flanked Pyron’s men and successful accomplished two retreats. During the second retreat, Chivington’s troops captured the Confederate’s rearguard; then he consolidated his troops and made camp at Kozlowski’s Ranch.
The following day, all was quiet on the battle front as both sides spent that time acquiring reinforcements. Lieutenant Colonel William R. Scurry brought in 800 Confederate troops to join Pyron, strengthening his numbers to approximately 1,100.
After assessing the situation, Colonel John Slough’s battle plan was to attack the Confederates the next day. Slough gave Chivington orders to circle around and attack the Confederate’s flank, while he and his troops would engage the Confederates from the front. Plans were also being hashed out in the Confederate camp; with Scurry planning an advance on the Union troops in the pass. As the sun rose on the morning of March 28, both sides made their move into Glorieta Pass.
1,300 troops, under the command of Slough, were involved in the battle which began late in the morning. As the afternoon wore on, the Yankees were pushed back even further down the pass. Scurry later discovered Slough’s Yankee troops headed towards his men, and quickly prepared a defense to receive them. Surprised by the fact the Confederates were already in the advanced position; Slough immediately realized a new strategy was required. Since Chivington would not be able to assist as previously planned, Slough moved forward and struck at Scurry’s line around 11:00 a.m.
As the battle progressed, attacks and counterattacks ensued with Scurry’s men having the upper hand the majority of the time. Unlike battle procedures in the East, the broken terrain of Glorieta Pass caused the fighting to be concentrated into smaller unit actions. Eventually Scurry obtained a tactical victory by forcing Slough's men to fall back to Pigeon Ranch, and then Kozlowski's Ranch.
Even though he was not in a position to help Slough’s attack, Chivington was not idle in his efforts. Rather than rush to the sound of the guns, Chivington headed off in a different direction. Following a brief skirmish at Johnson’s Ranch, the Yankees were finally able to snatch victory from the jaws of defeat and stand their ground. It was during that time Chivington’s troops were able to attack a Confederate supply train. In the process, 90 wagons were burned and 800 animals slaughtered. The destruction of their supplies forced the Confederates to withdraw and return to Santa Fe. In the process, 36 Confederate troops were killed, 70 were wounded and 25 taken prisoner. Union losses totaled 38 killed, 64 wounded and 20 captured.
Following a week in Santa Fe, the Confederates withdrew down the Rio Grande, never to be seen again in the region throughout the remaining course of the war. By June, New Mexico was under full control of the Yankees. The defeat of Sibley's New Mexico Campaign successfully demolished Confederate hopes in the Southwest, allowing the area to remain in Union hands for the duration of the war. Due to the decisive nature of the battle, it is sometimes referred to as the "Gettysburg of the West."