See biography by D. L. Clarke (1961).
Stephen Watts Kearny (IPA: [ˈkɑɹni]; "Kar-ney") (August 30, 1794 October 31, 1848) was one of the foremost antebellum frontier officers of the United States Army, and is remembered for his significant role in the Mexican-American War, especially the conquest of California. The Kearny code, which sought to govern government behavior towards Californios, was named after him.
In 1826, Kearny was appointed as the first commander of the new Jefferson Barracks in Missouri. While stationed there, he was often invited to nearby Missouri. By way of Meriwether Lewis Clark, Sr., he was invited as a guest of William Clark of the Lewis and Clark Expedition. He met later and married Clark's stepdaughter, Mary Radford. The couple had eleven children, though several died in childhood.
While at the Jefferson Barracks, Kearny organized a regiment of dragoons on the lines of a cavalry unit. The U.S. Cavalry eventually grew out of this regiment, earning Kearny his nickname as the "father of the United States Cavalry". The regiment was stationed at Fort Leavenworth in present-day Kansas, and Kearny was promoted to the rank of Colonel. 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.
By the early 1840s, when emigrants began traveling along the Oregon Trail, he often ordered his men to escort them across the plains so they could avoid attack by the Native Americans. The practice of military escorting wagon trains would become official government policy in succeeding decades. To protect the emigrants, Kearny established a new post along Table Creek near present-day Nebraska City, Nebraska. The outpost would be named Fort Kearny. 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.
At the outset of the Mexican-American War, Kearny marched to Santa Fe, New Mexico at the head of a force of 1,700. His Army of the West consisted of two regiments of Missouri volunteers, a regiment of New York volunteers (who would travel by ships to California), artillery and infantry battalions, 300 of Kearny's own 1st Dragoon Regiment, and the famous Mormon Battalion. Kearny easily took control of the area and was named its military governor on August 18, 1846. He ensured that a civilian government was in place within just one month.
Kearny then set out for California on September 25 with a force of only 300 men. En route he learned that California was presumedly under American control so he sent 200 dragoons back to Santa Fe. His weary 100 dragoons, having suffered along the way, narrowly defeated a Californio-Mexican cavalry under Andres Pico at the Battle of San Pasqual. Kearny himself was slightly wounded. However, he was able to unite with naval forces who were in San Diego, under the command of Commodore Robert F. Stockton. The combined Army and Navy force consolidated its control over San Diego in December, and in January 1847 won the battles of San Gabriel and La Mesa taking control of Los Angeles.
Kearny, as ranking Army officer, claimed command of the area at the end of hostilities, which began an unfortunate rivalry with Stockton. When Mexican forces in California capitulated on January 13. However, they did not do so to Stockton or Kearny, but to Stockton's aide, Lt. Col. John C. Frémont. Stockton seized on this and appointed Frémont military governor of the area. Kearny appealed to Washington. Receiving confirmation of his authority, Kearny took command. He had Frémont relieved, arrested, and later convicted at a court-martial, though Frémont quickly received a presidential pardon.
His nephew was Major General Phillip Kearny , III of American Civil War fame.
Kearny is the namesake of Kearny, Arizona and Kearney, Nebraska. Many schools are named after Kearny, including Kearny Elementary in Santa Fe, New Mexico and Kearny High School in Kearny Mesa, San Diego, California. Kearny Street, in downtown San Francisco, is also named for him, as is a street in Fort Leavenworth. Prior to 1947, what is today Marine Corps Air Station Miramar was called Camp Kearny.