Pacific Coast Campaign

The Pacific Coast Campaign refers to United States naval operations against targets along Mexico's Pacific Coast during the Mexican-American War. It excludes engagements of the Conquest of California in Alta California. The objective of the campaign was to secure the Baja California peninsula, blockade or capture west coast ports of Mexico and especially capture Mazatlan, a major Mexican seaport used for imported supplies. The resistance of the Californios in Alta California and the lack of ships, soldiers and logistical support prevented an early occupation of Baja California Sur and the west coast seaports of Mexico. The U. S. Navy blockaded the ports three times before being able to successfully blockade or occupy them.

Following an easy occupation at first, due to the capitulation of La Paz by Governor Col. Francisco Palacios Miranda, loyal Bajacalifornios met and declared Miranda a traitor and rose in revolt under a new governor, Maurico Castro Cota and then under the leadership of Manuel Pineda Munoz who defended Mulege from American landings, then attempted to expel the Americans from La Paz and San Jose del Cabo. Pineda was eventually captured and the Mexican army under Cota finally defeated at Todos Santos but only after the peace treaty that ended the war returned the captured regions south of Alta California to Mexico.

Following the July to August 1846 campaign of the Conquest of California Commander of the Pacific Squadron, proclaimed United States control of Alta California, on August 17, 1846. Following this, Commander Stockton, on August 19, ordered Joseph B. Hull, commander of the USS Warren, to blockade Mazatlan. Samuel F. Dupont, commander of the second class sloop-of-war Cyane, was ordered to blockade San Blas, about 125 miles south of Mazatlan. Stockton intended to seize Acapulco, and use it as a base for a joint Army-Navy expedition into Mexico. On September 2, 1846 the Cyane captured two Mexican vessels in the harbor then a landing party spiked 34 cannons in the port of San Blas. On September 7, the Warren seized the Mexican brig Malek Adhel at Mazatlan.

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