"It is our manifest destiny to overspread and possess the whole of the continent which Providence has given us for the great experiment of liberty...."

— John L. O'Sullivan, Editor
New York Morning News, 1845

This ringing phrase — Manifest Destiny — was immediately picked up as a campaign slogan by James K. Polk, then running for president, and soon echoed in the halls of Congress. Senator Thomas Hart Benton of Missouri used it to justify taking Indian lands and Mexican provinces and overrunning everyone who dared defy "God's will." It would describe a whole age of rapid expansionism.

The apple of Senator Benton's eye was his daughter, Jessie, who displeased her father to no end by marrying an army lieutenant eleven years her senior. He was John Charles Frémont, who would come to symbolize Manifest Destiny even more than Benton or Polk. Frémont would leave his name on mountains, towns and even the pass between the Santa Clarita and San Fernando valleys.

During a series of highly publicized expeditions Frémont mapped the Missouri River, the Oregon Trail and the northern Sierra Nevada. The press dubbed him "The Pathfinder," even though Kit Carson was his guide and found most of the paths.

Campo de Cahuenga memorial to the Treaty of Cahuenga, by which the United States acquired California. Fremont and Pico signed the treaty Jan. 13, 1847, at this location - now 3919 Lankershim Blvd., across the street from Universal City. (Uncredited L.A. Times photograph, 2/3/1956, out of copyright, in UCLA Library. Click image to enlarge.)

On May 13, 1846, President Polk's war with Mexico was declared official by Congress, at which time Brevet Major Frémont and sixty-two members of his "map making" expedition were dashing into Mexican California from Oregon. Frémont had already clashed with Mexican officials and had been asked to leave the country. Dispatches from the President and his father-in-law brought him rushing down to Sutter's Fort in the Sacramento Valley in time to bolster the Bear Flag Revolt.

Most Californios were dissatisfied with Mexican rule and were willing to hand over the province peacefully until Frémont fortified Hawk's Peak in the Gavilan Mountains. The Bear Flaggers made things worse when they kidnapped the venerable Mariano Vallejo, and one Archibald Gillespie antagonized Los Angeles with his high-handed methods.

War broke out, climaxed by Generál Andrés Pico defeating General Kearny at the Battle of San Pasqual, northeast of San Diego. Meanwhile, Frémont and his hundred-man "buckskin battalion" marched southward along the coast, arriving at Castaic Junction on the evening of January 9, 1847.

Edwin Bryant, a member of the battalion, wrote that "we encamped this afternoon at a rancho situated on the edge of a fertile and finely-watered plain of considerable extent, where we found corn, wheat and frijoles in great abundance. The rancho was owned by an aged Californian of commanding and respectable appearance." This must have been the forty-five-year-old Don José Salazár.

"On January 10," young Bryant continues, "crossing the plain we encamped, about 2 p.m. in the mouth of a cañada, through which we ascended over a difficult pass in a range of elevated hills between us and the plain of San Fernando."

Three days later Andrés Pico met with Frémont's forces at the home of María Jesus Lopez de Felíz. There Pico handed over his sword and ended the war in California. Known as the Capitulation of Cahuenga, it was indeed, to Frémont's credit, "peace with honor."

The Treaty of Guadalupe Hidalgo, signed February 2, 1848, officially ceded Texas, New Mexico, Arizona and California to the United States.