Louisville, largest city in Kentucky, U.S., and the seat of Jefferson county, opposite the Falls of the Ohio River. Louisville is the centre of a metropolitan area including Jefferson county in Kentucky and Clark and Floyd counties in Indiana. Bridges spanning the Ohio link the city with New Albany and Jeffersonville, Indiana. Following a referendum passed in 2000, the city and Jefferson county merged in 2003, thereby more than doubling the city’s population and increasing its area more than sixfold.
The first recorded visit to the area by Europeans was on July 8, 1773, when Captain Thomas Bullitt arrived to survey the lands with a commission from the governor of Virginia. During the American Revolution, a group of settlers accompanying the American officer George Rogers Clark settled (May 1778) on Corn Island (since swept away by floods) opposite Beargrass Creek, where Clark organized a base for the conquest of the British-held Old Northwest. Most of the settlers who came with him moved ashore the following winter and established Fort-on-Shore (Fort Nelson) within the present city limits. The town was organized in 1779 and named for Louis XVI of France; it was incorporated as a town the following year.
By 1811 Louisville had become an important frontier and river-flatboat trading place, and its development was further stimulated that year when Captain Nicholas Roosevelt docked the New Orleans, the first successful steamboat to ply the waters of the Ohio and Mississippi rivers. The city had become a major river port by 1820, and further stimulation came about with the construction (1825–30) of the canal around the 25-foot- (8-metre-) high Falls. Louisville’s commercial influence extended over a vast area of the South and the Midwest. During the American Civil War, the city served as a military headquarters and a major Union supply depot. It escaped the ravages of war and became an important way station for slaves seeking freedom in Indiana, across the river. A vigorous campaign to reclaim the South’s trade followed the war. In the 1880s the Louisville and Nashville Railroad was extended to Jacksonville, Florida.
The city’s economy was boosted during World War I when Camp Zachary Taylor was built nearby, and, later, when Fort Knox (30 miles [48 km] to the southwest) was enlarged. Periodic flooding of the Ohio necessitated extensive protection work; a destructive flood in 1937 caused widespread damage.
New industries were established during World War II, notably the production of synthetic rubber. The city is a leading producer of bonded bourbon whiskey and cigarettes. In addition to synthetic rubber, other products include paint and varnish, aluminum items, appliances, automobiles, pottery, and printed matter. Services are increasingly important, notably health care administration, and Louisville International Airport is a national hub of air cargo traffic. Tourism is also an important component of the economy. The American Printing House for the Blind (1858), which publishes books in Braille, is located in Louisville, as is the headquarters of the Hillerich & Bradsby Company, makers of the famed Louisville Slugger baseball bats (although most bats are now made elsewhere).
The University of Louisville was founded in 1798 as Jefferson Seminary. The city is also the seat of two Roman Catholic institutions—Spalding University (1814) and Bellarmine College (1950). Southern Baptist (1859) and Louisville Presbyterian (1853) theological seminaries are also in the city. The J.B. Speed Art Museum and the Louisville Science Center are other notable institutions.
As the scene of the annual Kentucky Derby, held every May at Churchill Downs since 1875, the city’s name has become synonymous with horse racing. The Kentucky State Fair, one of the oldest agricultural fairs in the United States, features an annual horse show that closely rivals the Derby in interest. Many historic buildings, including the homes of George Rogers Clark and an early residence of inventor Thomas Edison, are open to the public. The stern-wheeler Belle of Louisville holds its annual race with the Delta Queen during the Kentucky Derby Festival. Inc. city, 1828. Pop. (2000) 256,231; Louisville–Jefferson county Metro Area, 1,161,975; (2020) 246,161; Louisville–Jefferson county Metro Area, 1,283,566.