The Pacific Coast Campaign refers to United States naval operations against targets along Mexico's Pacific Coast during the Mexican–American War. The objective of the campaign was to secure the Baja Peninsula of Mexico, and to blockade/capture west-coast ports of Mexico—especially Mazatlan, a major port-of-entry for imported supplies. The resistance of Mexican forces to the north in the Los Angeles area and the lack of ships, soldiers and logistical support prevented an early occupation of the peninsula and the west-coast Mexican seaports. The U.S. Navy attempted blockades of the ports three times before being able to successfully blockade and/or occupy them.

Following an easy initial occupation and the capitulation of La Paz by Governor Col. Francisco Palacios Miranda, loyalist residents met, declared Miranda a traitor, and rose in revolt. Under a new governor, Mauricio Castro Cota, and then under the leadership of Manuel Pineda Munoz (who defended Mulege from American landings), the loyalists attempted to expel the Americans from La Paz and San José del Cabo. Pineda was eventually captured and the Mexican army under Cota finally defeated at Todos Santos but only after the Treaty of Guadalupe Hidalgo that ended the war returned captured regions south of San Diego to Mexico.