Conquest of California

Conquest of California
	Part of the Mexican–American War
	Top: Battle of Río San Gabriel; Bottom: Battle of San Pasqual
Date	15 June 1846 – 13 January 1847; (6 months, 4 weeks and 2 days);
Location	Northern Theatre:; San Francisco North Bay Area, Monterey Bay, Santa Clara Valley, Salinas Valley; Southern Theatre:; San Diego Bay, Los Angeles Basin, Pomona Valley, Santa Barbara, San Pasqual Valley
Result	American victory; Treaty of Cahuenga Full results American Military Government Installed in Alta California; Californio Loss of Power and Influence in California; Beginning of the California genocide; Major American Migration to the West; Displacement of Mexican Calfornios & Native Americans; Constitution of California, 1849; Eventual Californian statehood; ;
Territorial; changes	Mexican Cession (1848)
Belligerents
United States; California Republic;	Mexico
Commanders and leaders
John C. Frémont; Robert F. Stockton; Stephen W. Kearny; William B. Ide; John D. Sloat; John B. Montgomery; Archibald Gillespie ; Benjamin Wilson ; William Mervine ; James F. Reed	José Castro; José María Flores; Andrés Pico ; Mariano Vallejo ; Pío Pico; Joaquín de la Torre; José de Jesús Noé; José del C. Lugo; José Antonio Carrillo; Francisco Sánchez
Units involved
Units California Republic ; Bear Flag Rebels ; United States ; California Battalion ; Army of the West Naval units; Pacific Squadron Occupation units; Mormon Battalion; 7th Regiment of New York Volunteers ;	Units Mexico ; Castro Battalion ; P. Pico Battalion ; Flores Battalion ; Local Town Militias Cavalry units; A. Pico Lanceros; Lugo Lanceros; Carrillo Lanceros ;
Strength
USA; Initial strength: 30–300 militia; Horses and Mules; Native American Scouts; Peak strength: 2,000+ personnel (1847);	Mexico; Initial strength: 260–500 militiamen; 1 swivel Canon; ; Horses and Mules; Peak strength: 500 personnel (Jan. 1847);
Casualties and losses
California Republic: 1–2 killed; 3–7 wounded; 2 captured or missing; ; United States: ~35–40 killed; ~53–64 wounded; 25 captured or missing; ;	Mexico: ~11–14 killed; ~40–60 wounded; 2–3 captured or missing; ;

The Conquest of California, also known as the Conquest of Alta California or the California Campaign, was a military campaign during the Mexican–American War carried out by the United States in Alta California (modern-day California), then part of Mexico, lasting from 1846 to 1847, and ending with signing of the Treaty of Cahuenga by military leaders from both the Californios and Americans.