Los Osos was originally home to the Chumash Indians until European explorers, led by Don Gaspar de Portolà, arrived on September 7 – 8, 1769 traveling through the San Luis Obispo area on his way to rediscover the Bay of Monterey. Finding an abundance of bears in the area, his diarist, Padre Juan Crespi, O.F.M., recorded that the name given the area by his soldiers was "Los Osos".
The Valley changed ownership many times in its early history; and on September 24, 1845, Governor Pio Poco granted the land to John Wilson and James Scott. By the year 1882, the area was known as Los Osos after the now extinct California Grizzly. At this time, the valley was dotted with small farms and dairies. Los Osos/Baywood Park had its beginnings as a residential community back in 1919 when Walter Redfield bought 3000 lots of "useless sagebrush land" and advertised to vacationers from Southern California. However, the growth of the Los Osos/Baywood Park area didn't take off until the 1970's and 1080's. This small community now has three elementary schools, markets, a community center and library.