Commodore John Drake Sloat, upon hearing of imminent war and the revolt in Sonoma, ordered his naval and marine forces to occupy Yerba Buena (present-day San Francisco) on July 7 and raise the flag of the United States; this was accomplished on July 9. On July 15, Sloat transferred his command to Commodore Robert F. Stockton, a much more aggressive leader, who put Frémont's forces under his orders. On July 19, Frémont's "California Battalion" swelled to about 160 additional men from newly-arrived settlers near Sacramento, and he entered Monterey in a joint operation with some of Stockton's sailors and marines. The word had been received: war was official. The U.S. forces easily took over the north of California; within days they controlled San Francisco, Sonoma, and the privately owned Sutter's Fort in Sacramento.