Rancho Temescal was a farming outpost of Mission San Luis Rey de Francia, one of the 21 Franciscan missions established in California by Spain during the late 18th and early 19th centuries. The Mission was located on the coast where Oceanside, California, is today. The Rancho was settled in 1819 by Leandro Serrano, and became the first non-native settlement within the boundaries of what would become Riverside County, California.

Rancho La Sierra was a 17,769-acre (71.91 km2) Mexican land grant in present-day Riverside County, California, United States. In 1846 governor Pio Pico issued the grant to Bernardo Yorba. The grant lay between Rancho Jurupa and Rancho El Rincon, and included the present-day city of Corona.