It is considered a major Confederate success in the New Mexico Campaign of the American Civil War, despite the invading force abandoning the field.

Confederate brigadier general Henry Hopkins Sibley envisioned invading New Mexico with his army, defeating Union forces, capturing the capital city of Santa Fe, and then marching westward to conquer California for the Confederacy.

Sibley's first step was to gather an army in El Paso, Texas, and lead it north through Confederate Arizona to Fort Thorn.

Judging the fort to be too strong to be taken by assault, Sibley deployed his brigade in a line for the next three days, hoping to lure the Federals into the open, but Canby, not trusting his volunteer troops, refused to attack.

[9] As they were down to a few days' rations, the Confederates could not wait indefinitely, so at a council of war on the 18th, Sibley ordered the army to cross the Rio Grande and move up the eastern side of the river to the ford near Valverde, six miles north of Fort Craig, hoping to cut Union communications between the fort and their headquarters in Santa Fe.

[citation needed] By early afternoon, the remainder of the Confederate force, the 5th Texas Mounted Rifles under Colonel Thomas Green and a battalion of the 7th Texas Mounted Rifles under Lieutenant Colonel John Sutton, arrived at the battlefield, much in need of water and denied access to the river by the defending Union forces.

The soldier was not really paying attention to the gunfire, when the same rebel suddenly jumped up from his cover and fired six more shots from his revolver, none of them hitting the Coloradan.

[20] At this time, Green ordered the Confederate right wing under the command of Scurry to charge the Union center and the battery on its left; the attack force of 750 men was arranged into three successive waves.

[23] The Confederates were motivated, in large part, by their desperate need for water which could only be reached by dislodging the Union troops blocking their access to the Rio Grande.

[24] The Federals countered with a cavalry charge, but the main Confederate force continued to press their assault on Canby's left flank, capturing six artillery pieces and breaking the Union battle line, which soon turned into a panic-stricken retreat of both regular troops and New Mexico volunteers.

Canby managed to reorganize his men, minus about 200 deserters from among the New Mexico volunteers, and ordered a retreat back to Fort Craig leaving the road northward toward Santa Fe open to the Confederates.

[citation needed] Left in possession of the battlefield, the Confederates gained a victory but had suffered substantial casualties, reporting 36 killed, 150 wounded, and one missing out of 2,590 men.

However, he was severely hampered by the losses in horses and mules from the battle, which forced him to dismount the 4th Texas as infantry and to destroy some supplies and wagons.

[30] Considering himself to be outnumbered, he chose not to pursue Sibley, instead sending mounted detachments of New Mexico volunteers against the Confederates' rear for harassment and orders to Albuquerque and Santa Fe to destroy all supply depots and other means the invaders might support themselves.

Canby blamed the New Mexican volunteers, mostly Hispanics, for his loss—but his decision to reinforce his right while weakening his center and left was the real cause of the Union defeat.