Stephen Watts Kearny (sometimes spelled Kearney) (/ˈkɑːrni/ KAR-nee)[2] (August 30, 1794 – October 31, 1848) was one of the foremost antebellum frontier officers of the United States Army.

The Kearny Code, proclaimed on September 22, 1846, in Santa Fe, established the law and government of the newly acquired territory of New Mexico and was named after him.

His father, who was of Irish ancestry (the family name had originally been O'Kearny), was a successful wine merchant and landowner in Perth Amboy, New Jersey, before the start of the American Revolution (1775–83).

On 13 October 1812 during the Battle of Queenston Heights, Kearny and Lieutenant Colonel Winfield Scott led a charge, which took the British position; but the enemy retook it, when the "untrained militiamen"[6] did not reinforce the U.S.

He was assigned to the western frontier under command of Gen. Henry Atkinson, and in 1819 he was a member of the expedition to explore the Yellowstone River in present-day Montana and Wyoming.

He was also made commander of the Army's Third Military Department, charged with protecting the frontier and preserving peace among the tribes of Native Americans on the Great Plains.

However, the Army realized the site was not well-chosen, and the post was moved to the present location on the Platte River in central Nebraska.

In May 1845, Kearny marched his 1st Dragoons of 15 officers and 250 men in a column of twos out the gates of Ft. Leavenworth for a nearly four-month-long reconnaissance into the Rocky Mountains and the South Pass, "the gateway to Oregon."

The Dragoons traveled light and fast, hauling 17 supply wagons, driving 50 sheep, and 25 beefs on the hoof (cattle).

"Barely two weeks later Kearny and his troopers stood atop South Pass, held a regimental muster on the continental divide, and turned toward home.

"[12] Marching his Dragoons down the Rocky Mountains, past the future site of Denver Colorado, then Bent's Fort, then onto the Santa Fe Trail.

"[13] At the outset of the Mexican–American War, Kearny was promoted to brigadier general on June 30, 1846, and took a force of about 2,500 men to Santa Fe, New Mexico.

The next year, in 1847, three men pressed the case for the restoration of New Mexico's statehood and its admission to the American Union: Zachary Taylor, Abraham Lincoln, and Kearny's rival, John Charles Frémont.

On a trip across the Colorado Desert[19] to San Diego Kearny encountered marine Major Archibald H. Gillespie and about 30 men with news of an ongoing Californio revolt in Los Angeles.

In January 1847 a combined force of about 600 men consisting of Kearny's dragoons, Stockton's marines and sailors, and two companies of Frémont's California Battalion won the Battle of Rio San Gabriel and the Battle of La Mesa and retook control of Los Angeles on January 10, 1847.

Kearny and Stockton decided to accept the liberal terms offered by Frémont to terminate hostilities, despite Andrés Pico's breaking his earlier, solemn pledge that he would not fight U.S. forces.

Three private merchant ships, Thomas H Perkins, Loo Choo and Susan Drew, were chartered, and the sloop USS Preble was assigned convoy detail.

The companies were then deployed throughout Upper (Alta) and Lower (Baja) California from San Francisco to La Paz, Mexico.

With all these reinforcements in hand Kearny assumed command, appointed his own territorial military governor and ordered Frémont to resign and accompany him back to Fort Leavenworth, Kansas.

[23] In 1847 Frémont purchased the Rancho Las Mariposas, a large land grant in the foothills of the Sierra Nevada mountains near Yosemite, which proved to be rich in gold.

He also received a brevet promotion to major general in September 1848, over the heated opposition of Frémont's father-in-law, Senator Thomas Hart Benton.

Camp Kearny in San Diego, a U.S. military base which operated from 1917 to 1946 on the site of today's Marine Corps Air Station Miramar, was named in his honor.

[27] Actor Robert Anderson (1920–1996) played General Kearny in the 1966 episode "The Firebrand" of the syndicated western television series, Death Valley Days.

The episode is set in 1848 with the establishment of California Territory and the tensions between the outgoing Mexican government and the incoming American governor.