With these vigorous preliminary measures the commodore's command came to an end. He had been for some time past in bad health, and when, late in July, the "Congress" arrived, under Commodore Stockton, a younger man and a most brilliant officer, Commodore Sloat turned over the command to him. The campaign had been opened, and it remained for the new commander-in-chief to follow up the blows that had been struck.
At this time the Californian Legislature was in session at Los Angeles, the capital of the province, which was defended by a body of Mexican troops under General Castro. Commodore Stockton at once determined to strike a decisive blow at the city. As Los Angeles was not on the sea-coast, and as it was defended by a trained army, it required an extraordinary degree of boldness and enterprise on the part of the naval commander to resolve to attack it without the aid of regular soldiers. But the result only shows how much may be done in case of necessity by blue-jackets on shore under a capable commander. The commodore organized the volunteer dragoons as a battalion of mounted riflemen, and appointed Captain Frémont major and Lieutenant Gillespie captain. On the day after he took command the battalion embarked on board the "Cyane," and next day it sailed for San Diego, from which place it was to march toward the capital. A few days later Commodore Stockton sailed in the "Congress" to San Pedro, a point some distance to the northward of San Diego, and only thirty miles from Los Angeles. On his way down he landed a garrison at Santa Barbara, an intermediate port. Arriving at San Pedro he organized a little army--a naval brigade, as we should call it now--of three hundred and fifty seamen and marines, drilling them daily on shore by a rough manual which he devised hastily for the purpose. For artillery he had some 6-pounders and a 32-pounder carronade.
After a few days' delay, to exercise his men and to give Major Frémont time to begin his advance, the commodore set out for Los Angeles. His force was only one third of that of the enemy, who were strongly intrenched in a fortified camp in the valley of the river Mesa. The road from San Pedro contained many narrow defiles, which the Mexicans might easily have defended; but, strange to say, they neglected this advantage. On his way Stockton was twice called upon to surrender by envoys from General Castro; but he talked to them so boldly that he succeeded in deceiving them about the actual size of his force. Soon they became alarmed at the invasion, and when the Americans arrived at Castro's camp, it was found that the general had fled, and that his followers were scattered in all directions. On the 13th of August the commodore entered Los Angeles and took possession of the capital of California.