Riverside County, California is one of fifty-eight counties in the state of California. Based on the 2010 census, the
population was 2,189,641, making it the 4th-most
populous county in California. The county seat
is Riverside. Riverside county was formed March 11,
1893. This county was created from portions of San Diego and San
Bernardino counties and derived its name from the City
of Riverside.
Riverside County is included in the Riverside-San Bernardino-Ontario, CA Metropolitan Statistical Area, also known as the Inland Empire. The
county is also included in the Los Angeles-Long Beach, CA Combined Statistical Area.
This county was created from portions of San Diego and San Bernardino counties and derived its name from the City of Riverside, christened when the upper canal of the Santa Ana River reached it in 1871.
County QuickFacts: CensusBureau Quick Facts
Riverside County is the fourth largest county in the state, 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 densely populated Los Angeles, Imperial, Orange, San Diego, and San Bernardino Counties...extending
from within 14 miles of the Pacific Ocean to the Colorado River.
The county takes 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.
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 caucasians to travel 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 1822, Mexico successfully revolted against Spain, 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, seekers of religious freedom, and individuals
desiring to create ideal colonies.
In May 1893, voters living within an area carved from San Bernardino County (to the north) and San Diego County (to the
south), 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 the agriculture
industry...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 to Riverside County. Between 1980 and 1990, the number of residents
grew by over 76%...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.
As reported by the Census Bureau, the county has a total area of 18,915 km2 (7,303 sq mi) of which 18,667 km2 (7,207 sq mi) is land and 248 km2 (96 sq mi), or 1.31%, is water.
At approximately 180 miles (290 km) wide in the east-west dimension, the area of the county is
huge.
County government documents often cite the Colorado River town of Blythe as being a "three-hour
drive" from the county seat, Riverside. Some view the areas west of San Gorgonio Pass as the Inland
Empire portion of the county and the eastern part as either the Mojave Desert or Colorado Desert
portion. There are probably at least three geomorphic provinces: the Inland Empire western portion, the
Santa Rosa Mountains communities, and the desert region. Other possible subdivisions include tribal
lands, the Colorado River communities, and the Salton Sink.
The Inland Empire area of southern California is made up of the western portion of Riverside County.
Bordering counties are as follows: