Prehistoric cultural affiliation(s) include Valley Nisenan Maidu dating back to 1000.
Several famous people are associated with these Placer County historic places including Griffith Griffith and Mark Hopkins.
Some of the country's most noteable architects helped create the Placer County places including US Bureau of Reclamation, Unkown, John B. Leonard, Griffith Griffith, Robert Montgomery Watson, Southern Pacific RR Co., Central Pacific Railroad Company, William V. Whitsell, Augustus E. Bond and Tony Perry. Prominent architectural styles found in Placer Country are Classical Revival, Beaux Arts and Stick/Eastlake.