Kings County is a county located in the Central Valley of the U.S. state of California. It is situated in a rich agricultural region. Kings County is also home to NAS Lemoore, which is the U.S. Navy's newest and largest master jet air station. The county seat is Hanford. The United States Census Bureau defines Kings County as encompassing the entire Hanford–Corcoran Metropolitan Statistical Area (MSA Code 25260). The population was 152,982 at the time of the 2010 U.S. Census. According to the California Department of Corrections and Rehabilitation, the county's population included 18,640 state prison inmates as of March 31, 2010. The California Department of Finance estimated that Kings County's population was 150,479 as of July 1, 2013. The inmate population had been reduced to 14,542 by July 1, 2013.
An 1805 expedition probably led by Spanish Army Lieutenant Gabriel Moraga recorded discovering the river, which they named El Rio de los Santos Reyes (River of the Holy Kings) after the Three Wise Men of the Bible. At the time of the United States conquest in 1848, the new government changed the name to Kings River after which the county was named.
In 1880, a dispute over land titles between settlers and the Southern Pacific Railroad resulted in a bloody gun battle on a farm northwest of Hanford; seven men died. This event became known as the Mussel Slough Tragedy.
Settlers reclaimed Tulare Lake and its wetlands for agricultural development. In surface area, it was formerly the largest body of freshwater west of the Great Lakes, and supported a large population of migratory birds as well as local birds and wildlife. Monoculture has sharply reduced habitat for many species.
In 1928, oil was discovered in the Kettleman Hills located in the southwestern part of Kings County. The Kettleman North Dome Oil Field became one of the most productive oil fields in the United States.
In 1933 during the Great Depression, cotton pickers in the southern San Joaquin Valley, mostly migrant Mexican workers, went on strike. During the strike, 3,500 striking farm workers lived in a four-acre camp on the land of a small farmer on the outskirts of Corcoran. Ultimately, the federal government intervened to force both sides to negotiate a settlement.
The completion of the California Aqueduct in the early 1970s brought needed water for agriculture and domestic use to the westside of the county.