It took place at a ford of the San Gabriel River, at what are today parts of the cities of Whittier, Pico Rivera and Montebello, about ten miles south-east of downtown Los Angeles.

Although Kearny had superior orders from the United States War Department, he had previously sent most of his troops back to Santa Fe, New Mexico, believing that the war in California had ended, and his remaining force sustained heavy losses at the Battle of San Pasqual.

[1]: 190 At approximately 2 pm, the Americans formed into a square when two miles from the river with the baggage and cattle in the middle, and sent skirmishers ahead.

[1]: 190  Flores attacked the square with horses, which failed, plus his makeshift ammunition and inadequate gunpowder proved to be ineffective.

[1]: 191 General Kearny's official report of the battle: Headquarters Army of the West, Ciudad de Los Angeles, Upper California, January 12, 1847.

SIR, -- I have the honor to report, that at the request of Commodore R. F. Stockton (who in September last assumed the titled of Governor of California), I consented to take command of an expedition to this place – capital of the country – and that on the 29th of December, I left San Diego with about five hundred men, consisting of sixty dismounted dragoons, under Captain Turner; fifty California volunteers, and the remainder of marines and sailors, with a battery of artillery.

We proceeded on our route without seeing the enemy till the 8th instant, when they showed themselves in full force of six hundred mounted men, with four pieces of artillery, under their Governor Flores, occupying the heights in front of us, which commanded the crossing of the river San Gabriel, and they ready to oppose our further progress.

The next day, the 9th instant, we proceeded on our march at the usual hour, the enemy in front and on our flanks, and when we reached the plains of the Mesa, their artillery again opened upon us, when their fire was returned by our guns as we advanced; and after hovering around and near us for about two hours, occasionally skirmishing with us during that time, they concentrated their force and made another charge on our left flank, which was quickly repulsed; shortly after which they retired, we continuing our march; and in the afternoon encamped on the bank of the San Fernando, three miles below this city, which we entered the following morning without molestation.

The enemy mounted on fine horses and being the best riders in the world, carried off their killed and wounded, and we know not the number of them, though it must have been considerable.

[1]: 194  Stockton, who had been the initial military governor of California, later granted that post to his aide, Lieutenant-Colonel (later General) John C.