Raising of the U.S. flag at Yerba Buena (July 9, 1846)

On July 9, 1846, sailors and marines from the U.S. Navy sloop-of-war USS Portsmouth landed at Yerba Buena and raised the U.S. flag, an act that asserted American control over the settlement. This event preceded the formal renaming of Yerba Buena to San Francisco and is commonly cited as the U.S. occupation of the town during the Mexican–American War. The landing and flag-raising are commemorated in Portsmouth Square, which occupies the historic site.