Fort Ross, known as the Russian fortress Ross in California, existed from 1812 to 1841. This settlement on the Northern California coast, located 80 km north of San Francisco, was founded in 1812 by the Russian-American Company for fur trading. Ross was the southernmost Russian settlement in North America. In 1841, the company sold it to the large landowner John Sutter. It is now a California state historic park and a U.S. national historic landmark.

The initiator of the fortress and settlement in California was A. A. Baranov. To choose a location for the settlement, several expeditions were conducted under the leadership of Ivan Kuskov, an employee of the Russian-American Company, in 1808, 1809, 1811, and 1812. Kuskov noted a plateau 30 km north of Rumyantsev Bay (now Bodega Bay), surrounded by deep ravines, forests, and pastures. Ten kilometers from it flowed a river, which he named Slavyanka (now Russian River). The fortress Ross saw the first windmills, shipyards, fruit orchards, and vineyards in California. Russian colonists brought many achievements of European civilization to California, such as window glass. In 1837 and 1840, Yegor Chernykh began the first systematic weather observations in California.

In 1839, the Russian-American Company decided to abandon Fort Ross and sell it. The Hudson's Bay Company showed no interest in the deal, and the Mexican government, considering the land its own, refused to pay, expecting the Russians to leave the colony. As a result, in 1841, Fort Ross was sold to American entrepreneur John Sutter.