The area in which today's San Pablo is situated was originally occupied by the Cuchiyun band of the Ohlone indigenous people. The area was claimed for the king of Spain in the late 18th century and was granted for grazing purposes to the Mission Dolores located in today's San Francisco. Upon Mexico's independence from Spain, church properties were secularized and in 1823, the area became part of a large grant to an ex-soldier stationed at the San Francisco Presidio, Francisco María Castro. The grant was given the name Rancho San Pablo, thus originating the name for today's city as well as for one of the East Bay's oldest principal roads, today's San Pablo Avenue (known during the Spanish colonial era as "El Camino Real de la Contra Costa").