U.S. takes San Francisco - Jul 09, 1846 - HISTORY.com

An American naval captain occupies the small settlement of Yerba Buena, a site that will later be renamed San Francisco.

Surprisingly, Europeans did not discover the spectacular San Francisco Bay until 1769, although several explorers had sailed by it in earlier centuries. When Spanish explorers finally found the bay in that year, they immediately recognized its strategic value. In 1776, the Spanish built a military post on the tip of the San Francisco peninsula and founded the mission of San Francisco de Asis (the Spanish name for Saint Francis of Assisi) nearby.

The most northern outpost of the Spanish, and later Mexican, empire in America, the tiny settlement remained relatively insignificant for several decades. However, the potential of the magnificent harbor did not escape the attention of other nations. In 1835, the British Captain William Richardson established a private settlement on the shore of Yerba Buena Cove, several miles to the east of the Mexican mission. That same year the U.S. government offered to purchase the bay, but the Mexicans declined to sell.

In retrospect, the Mexicans should have sold while they still had the chance. A little more than a decade later, a dispute between the U.S. and Mexico over western Texas led to war. Shortly after the Mexican War began, U.S. Captain John Montgomery sailed his warship into San Francisco Bay, anchoring just off the settlement of Yerba Buena. On this day in 1846, Montgomery led a party of marines and sailors ashore. They met no resistance and claimed the settlement for the United States, raising the American flag in the central plaza.

The following year, the Americans renamed the village San Francisco. When the Mexicans formally ceded California to the United States in the 1848 Treaty of Guadalupe, San Francisco was still a small town with perhaps 900 occupants. That same year, however, gold was discovered at the nearby Sutter’s Fort. San Francisco became the gateway for a massive gold rush, and by 1852, the town was home to more than 36,000.