Kearny Expedition

US #944 pictures the raising of the American flag above the governor’s palace in Santa Fe, New Mexico, in August 1846.

On August 18, 1846, Stephen W. Kearny declared himself military governor of the New Mexico Territory.  He had captured Santa Fe without firing a shot, as part of the Kearny Expedition.

Stephen Watts Kearny was born in Newark, New Jersey, in 1794.  He served with the 13th Infantry Regiment during the War of 1812 and would spend much of the next 30 years on the frontier.

US #970 was issued for the 100th anniversary of Fort Kearny.

During this time, he ordered his men to escort travelers along the Oregon Trail across the plains to avoid Native American attacks.  He established a post along the route, which was named in his honor.  The post was then moved to the Platte River in central Nebraska and was also called Fort Kearny.

US #970 – Plate Block First Day Cover

When the Mexican-American War broke out in 1846, Kearny was promoted to brigadier general.  He was ordered to lead an expedition from Fort Leavenworth, Kansas, to capture New Mexico and California for the United States.  Kearny had a force of about 2,500 men that were marching toward an unknown number of defending Mexicans.

The governor of Santa Fe didn’t want to fight but was convinced by his priests that they should defend the town.  They set up positions, but on August 14, before Kearny and his troops arrived, the governor changed his mind.  He ordered his men to retreat to Chihuahua.

US #1031A – Built in 1610, the Palace of the Governors is the oldest public building in the US.

Kearny and his men reached the town on August 15, but didn’t encounter any Mexican forces.  They claimed the New Mexico Territory for the United States without firing a single shot.  On August 18, 1846, Kearny declared himself the military governor of the New Mexico Territory.  He used the Palace of the Governors as his administrative center.  After taking control of Santa Fe, Kearny established a civil government and promised a democratic administration of the area.  These actions secured popular support for the US government and its troops.

Kearny then appointed a civil governor and set out for California on September 25 with 300 men.  Along the way, he met Kit Carson, who told him California was under American control, so Kearny sent back 200 of his men.  As he continued toward his destination, Kearny encountered another American soldier who said there was a revolt in Los Angeles.

US #1031A – Classic First Day Cover

On December 6, Kearny and his force of 100 men encountered a force of about 150 Californio Lancers.  The American troops’ powder was wet, so their guns wouldn’t fire.  About 18 of his men were killed and those remaining were forced to retreat.  Kit Carson managed to sneak away to San Diego and returned with reinforcements.  After driving the Californios back, Kearny’s troops and those from California then retook Los Angeles in January 1847.

US #944 – Classic First Day Cover

Kearny then served as military governor of California from February to May 1847.  He received a hero’s welcome in Washington, DC, and was then appointed the governor of Veracruz and later Mexico City.  He died the following year, on October 31, 1848.

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  1. The battle on December 6, 1847 was the Battle of San Pasqual. The commander of the Mexican lancers was Andres Pico. The battlefield is located in San Diego County and is now a state historic park.

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