Prehistoric cultural affiliation(s) include Cahuilla, European, Native American, Luiseno, San Dieguito, Early Playa, Malpais, Patayan and Amargosan dating back to 16999 BC.
The famous person James Marshall Gilman is associated with one of more of the Riverside County historic places.
Some of the country's most noteable architects helped create the Riverside County places including Myron Hunt, Unkown, US Army Quartermaster Corps, James Marshall Gilman, Walter R. Goss, Rocco Garbani, G. Stanley Wilson and Dwight Gibbs. Prominent architectural styles found in Riverside Country are Mission/Spanish Revival, Late 19th And Early 20th Century American Movements and Late Victorian.