After Mexico gained its independence from Spain in 1821, New Mexico came under Mexican rule, but it was no safer. Attacks by Apaches, Navajos and Comanches continued.

The ten soldiers assigned to Albuquerque at its founding had been withdrawn and were not replaced. The governments of New Mexico and Mexico had no money to hire solders. Spanish Governor Juan de Anza had made a treaty with the Comanches, which reduced their attacks, but the money used to maintain the Comanches’ friendship was also gone. The Navajos were raiding, stealing livestock, taking captives and killing in the Albuquerque area.

As it was in the previous 140 years, safety depended on the citizen and pueblo militia. During this period, attacks and counterattacks were frequent.

In 1835, the Mexican government appointed Albino Perez as governor of New Mexico. New Mexicans didn’t like Perez, who changed the government and increased taxes. The people formed a new army led by Manuel Armijo, an Albuquerque resident, which drove Perez from power. The Mexican government then appointed Armijo governor.

In May 1846 the United States declared war on Mexico. Col. Stephen Watts Kearny was chosen to invade and conquer New Mexico. Before long, an army of 1,700 American soldiers was about to enter New Mexico. On August 7, 1846, Armijo issued a proclamation asking the people to display the "highest and best devotion to home and country."

On August 10, Armijo asked the Departmental Assembly in Mexico for $1,000 to maintain the army, but the government couldn’t afford to honor his request. Armijo called up the militia and many men came forward, but they lacked adequate arms. Armijo knew the territory was in trouble.

When Kearny arrived in Las Vegas on August 15, Armijo had his army in place in Apache Canyon. His defenses and artillery were ready. He called his leaders together for one last meeting to discuss whether they should fight. The militia was untrained and poorly armed. Some of his men questioned their ability to defend themselves against an army while others argued against capitulation. Armijo sent his people home and fled to Mexico. The American army took New Mexico without any bloodshed.