Riverside County is the fourth largest county in the state by population, stretching nearly 200 miles across and comprising over 7,200 square miles of fertile river valleys, low deserts, mountains, foothills and rolling plains. Riverside County shares borders with Imperial, Orange, San Diego, and San Bernardino Counties, extending from within 14 miles of the Pacific Ocean to the Colorado River.
Taking its name from the City of Riverside, the county was formed in 1893 from a small portion of San Bernardino County and a larger part of San Diego County.
Although the county marks its political beginnings in 1893, the land was occupied long before Europeans and their descendants entered the areas by several Native American groups including the Serranos, the Luisenos, the Cupenos, the Chemehuevi, and the Cahuillas. One of the first Caucasian travellers through the area was Juan Bautista de Anza who led an overland expedition in 1774.
In the late 18th century, the Spanish mission fathers of San Gabriel (Los Angeles County), San Juan Capistrano (Orange County), and San Luis Rey (San Diego) began colonizing the land and gradually used the interior valley in what is now western Riverside County for raising grain and cattle. During this period, Spain claimed all of California and Mexico.
In the early 1820s, Mexican opposition leaders pronounced themselves free from Spanish rule, and California came under Mexican jurisdiction. The missions and their lands were secularized beginning in 1834 and the land was transferred as "grants" to Californians who were citizens of Mexico. The first land grant in what is now Riverside County, Rancho Jurupa, was given to Juan Bandini in 1838.
In 1848, with the signing of the Treaty of Guadalupe Hidalgo, California became a territory of the United States, and in 1850 California became a state. This event generated a steady flow of settlers into the area, including gold miners, entrepreneurs, health-seekers, speculators, politicians, adventurers, people seeking religious freedom, and individuals who envisioned utopian colonies.
In May 1893, voters living within an area carved from San Bernardino County and San Diego County approved formation of Riverside County. On May 9, 1893, the county officially formed and began charting a course under its newly elected Board of Supervisors. The county's early years were linked to agriculture but commerce, construction, manufacturing, transportation and tourism soon took hold, contributing substantially to the region's rapid growth.
Recent years have brought dramatic population growth. Between 1980 and 1990, the number of residents grew by over 76 percent, making Riverside the fastest-growing county in California. By 1992, the County was "home" to over 1.3 million residents, more than the entire population of 13 states, among them Maine, Nevada, Hawaii and New Hampshire. Since 1992, the population has nearly doubled.
County Administration Center
4080 Lemon St. Riverside, CA 92501
Phone: (951) 955-1000
TTY Users: 711