San Gabriel (Spanish for "St. Gabriel") is a city located in the San Gabriel Valley of Los Angeles County, California. At the 2010 census, the population was 39,718. San Gabriel was founded by the Spanish in 1771, when Mission San Gabriel Arcángel was established by Saint Junípero Serra. Through the Spanish and Mexican periods, San Gabriel played an important role in the development of Los Angeles and Californio society. Owing to the prominence of Mission San Gabriel in the region's history, it is often called the "birthplace of the Los Angeles region".