American Civil War: Battle of Glorieta Pass

John P. Slough
Brigadier General John P. Slough, USA. Photograph Source: Public Domain

The Battle of Glorieta Pass was fought March 26-28, 1862, during the American Civil War (1861-1865) and was the culminating engagement of the New Mexico Campaign. Pushing into the New Mexico Territory in early 1862, Brigadier General Henry H. Sibley sought to drive Union forces from the region and open a path to California. His initial actions proved successful and his troops won a victory at the Battle of Valverde in February. Pushing on, Sibley intended to capture the Union base at Fort Craig.

Recovering from the defeat at Valverde, Union forces led by Colonel John P. Slough and Major John Chivington, engaged the Confederates at Glorieta Pass in late March. Though the Confederates won a tactical victory at the pass, a column commanded by Chivington captured their supply train. The loss of their wagons and supplies compelled Sibley to withdraw from the region. The strategic victory at Glorieta Pass effectively secured control of the Southwest for the Union for the remainder of the war. As a result, the battle has sometimes, rather grandiosely, been referred to as the "Gettysburg of the West."

Background

In early 1862, Confederate forces under Brigadier General Henry H. Sibley began pushing west from Texas into the New Mexico Territory. His goal was to occupy the Santa Fe Trail as far north as Colorado with the intention of opening a line of communication with California. Advancing west, Sibley initially sought to capture Fort Craig near the Rio Grande.

Bust portrait of Major General Henry H. Sibley wearing his gray Confederate Army uniform.
Brigadier General Henry H. Sibley, CSA. Library of Congress

On February 20-21, he defeated a Union force under Colonel Edward Canby at the Battle of Valverde. Retreating, Canby's force took refuge at Fort Craig. Electing not to attack the fortified Union troops, Sibley pressed on leaving them in his rear. Moving up the Rio Grande Valley, he established his headquarters at Albuquerque. Sending his forces forward, they occupied Santa Fe on March 10.

Shortly thereafter, Sibley pushed an advance force of between 200 and 300 Texans, under Major Charles L. Pyron, over the Glorieta Pass at the southern end of the Sangre de Cristo Mountains. The capture of the pass would allow Sibley to advance and capture Fort Union, a key base along the Santa Fe Trail. Camping at Apache Canyon in Glorieta Pass, Pyron's men were attacked on March 26 by 418 Union soldiers led by Major John M. Chivington.

Battle of Glorieta Pass

  • Conflict: American Civil War (1861-1865)
  • Date: March 26-28, 1862
  • Armies and Commanders:
  • Union
  • Colonel John P. Slough
  • Major John Chivington
  • 1,300 men
  • Confederates
  • Major Charles L. Pyron
  • Lieutenant Colonel William R. Scurry
  • 1,100 men
  • Casualties:
  • Union: 51 killed, 78 wounded, and 15 captured
  • Confederate: 48 killed, 80 wounded, and 92 captured

Chivington Attacks

Assaulting Pyron's line, Chivington's initial attack was beaten back by Confederate artillery. He then split his force in two and repeatedly flanked Pyron's men forcing them to retreat twice. As Pyron fell back a second time, Chivington's cavalry swept in and captured the Confederate rearguard. Consolidating his forces, Chivington went into camp at Kozlowski's Ranch.

On the following day the battlefield was quiet as both sides were reinforced. Pyron was augmented by 800 men led by Lieutenant Colonel William R. Scurry, bringing Confederate strength to around 1,100 men. On the Union side, Chivington was reinforced by 900 men from Fort Union under the command of Colonel John P. Slough. Assessing the situation, Slough planned to attack the Confederates the next day.

Chivington was given orders to take his men in a circling movement with the goal of striking the Confederate flank as Slough engaged their front. In the Confederate camp, Scurry also planned an advance with the goal of attacking at the Union troops in the pass. On the morning of March 28, both sides moved into Glorieta Pass.

A Close Fight

Seeing the Union troops moving towards his men, Scurry formed a line of battle and prepared to receive Slough's attack. Surprised to find the Confederates in an advanced position, Slough realized that Chivington would not be able to assist in the assault as planned. Moving forward, Slough's men struck at Scurry's line around 11:00 AM.

In the battle that followed, both sides repeatedly attacked and counterattacked, with Scurry's men getting the better of the fighting. Unlike the rigid formations used in the East, the fighting in Glorieta Pass tended to be focused on small unit actions due to the broken terrain. After forcing Slough's men to fall back to Pigeon Ranch, and then Kozlowski's Ranch, Scurry broke off the fighting happy to have achieved a tactical victory.

While the battle was raging between Slough and Scurry, Chivington's scouts succeeded in locating the Confederate supply train. Out of position to assist in Slough's attack, Chivington elected not to rush to the sound of the guns, but rather advanced and captured the Confederate supplies after a brief skirmish at Johnson's Ranch. With the loss of the supply train, Scurry was forced to withdraw despite having won a victory in the pass.

Aftermath

Union casualties at the Battle of Glorieta Pass numbered 51 killed, 78 wounded, and 15 captured. Confederate forces suffered 48 killed, 80 wounded, and 92 captured. While a tactical Confederate victory, the Battle of Glorieta Pass proved to be a key strategic win for the Union.

Due to the loss of his supply train, Sibley was forced to withdraw back to Texas, ultimately arriving at San Antonio. The defeat of Sibley's New Mexico Campaign effectively ended Confederate designs on the Southwest and the area remained 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."