The Inland Empire (commonly abbreviated as the IE) is a metropolitan area and region inland of and adjacent to coastal Southern California in the Greater Los Angeles area, focusing around the cities in Riverside and San Bernardino county with Los Angeles County and Orange County to the west. The region, at its narrowest definition, includes the cities of northwestern Riverside County and southwestern San Bernardino County that are part of the contiguous urbanized area of Greater Los Angeles. It is sometimes considered to include the desert communities of the Coachella and Victor Valleys, respectively on the other sides of the San Gorgonio Pass and San Bernardino Mountains from the Santa Ana River watershed that creates the majority of the Inland Empire. A much wider definition includes the entireties of Riverside and San Bernardino counties, stretching east to the Nevada and Arizona borders and covering a larger area than West Virginia; this definition is primarily used by the US Census Bureau, which exclusively delineates metropolitan areas at the county level.
The U.S. Census Bureau–defined Riverside–San Bernardino–Ontario metropolitan area, which comprises Riverside County and San Bernardino, California, covers more than 27,000 sq mi (70,000 km) and had a population of about 4.6 million in 2020. At the end of the 19th century, the Inland Empire was a major center of agriculture, including citrus, dairy and winemaking. Agriculture declined through the 20th century and a rapidly increasing population, helped by families migrating in search of affordable housing, has led to more residential, industrial and commercial development since the 1970s.
