In 1786 French explorer, the Comte de la Pérouse visited San Francisco and left a detailed account of it. Six years later, in 1792 British explorer George Vancouver also stopped in San Francisco, in part, according to his journal, to spy on the Spanish settlements in the area. In addition to Western European sailors, Russian colonists also visited the Bay area. From 1770, lasting through 1841, Russia colonized an area that ranged from Alaska south to Fort Ross in Sonoma County, California. The naming of San Francisco's Russian Hill neighborhood is attributed to the remains of Russian fur-traders and sailors found there.
View of Presidio of San Francisco circa 1817 by Louis Choris
Upon independence from Spain in 1821, the area became part of Mexico. In 1835, Englishman William Richardson erected the first significant homestead outside the immediate vicinity of the Mission Dolores, near a boat anchorage around what is today Portsmouth Square. Together with Mission Alcalde Francisco de Haro, he laid out a street plan for the expanded settlement, and the town, named Yerba Buena after the herb, which was named by the missionaries that found it abundant nearby, began to attract American settlers. In 1838, Richardson petitioned and received a large land grant in Marin County and, in 1841, he moved there to take up residence at Rancho Sauselito. Richardson Bay to the north bears his name.
The British Empire briefly entertained the idea of purchasing the bay from Mexico in 1841, claiming it would "Secure to Great Britain all the advantages of the finest port in the Pacific for her commercial speculations in time of peace, and in war for more easily securing her maritime ascendency". However little came of this, and San Francisco would become a prize of the United States rather than that of British naval power.
On July 31, 1846, Yerba Buena doubled in population when about 240 Mormon pioneers from the East coast arrived on the ship Brooklyn, led by Sam Brannan. Brannan, also a member of the Mormon Church, would later become well known for being the first publicist of the California Gold Rush of 1849 and the first millionaire resulting from it.
Portsmouth Square, 1851.
US Navy Commodore John D. Sloat claimed California for the United States on July 7, 1846, during the Mexican-American War, and US Navy Captain John Berrien Montgomery and US Marine Second Lieutenant Henry Bulls Watson of the USS Portsmouth arrived to claim Yerba Buena two days later by raising the flag over the town plaza, which is now Portsmouth Square in honor of the ship. Henry Bulls Watson was placed in command of the garrison there. In August 1846, Lt. Washington A. Bartlett was named alcalde of Yerba Buena. On January 30, 1847, Lt. Bartlett's proclamation changing the name Yerba Buena to San Francisco took effect. The city and the rest of California officially became American in 1848 by the Treaty of Guadalupe Hidalgo, which ended the Mexican-American War. California was admitted to the U.S. as a state on September 9, 1850 - the State of California soon chartered San Francisco as both a City and a County.
Situated at the tip of a windswept peninsula without water or firewood, San Francisco lacked most of the basic facilities for a nineteenth century settlement. These natural disadvantages forced the town's residents to bring water, fuel and food to the site. The first of many environmental transformations was the city's reliance on filled marshlands for real estate. Much of the present downtown is built over the former Yerba Buena Cove, granted to the city by military governor Stephen Watts Kearny in 1847.