Louisiana has a long and varied history. The region was possibly visited by Cabeza de Vaca and his fellow survivors of a Spanish expedition of 1528, and it was certainly seen by some of De Soto's men (1541–42). In 1682, La Salle reached the mouth of the Mississippi and claimed for France all of the land drained by that river and its tributaries, naming it Louisiana after Louis XIV. Europeans did not permanently settle there until 1699, when Pierre le Moyne, sieur d'Iberville, founded a settlement near Biloxi. This settlement became the seat of government for Louisiana, an enormous territory embracing the entire Mississippi drainage basin.
In 1702, Iberville's brother, the sieur de Bienville, was appointed governor and moved the territorial government to Fort Louis on the Mobile River. This colony was later moved (1710) to the present site of Mobile (Alabama), and Mobile became the capital of Louisiana. French missionaries and fur traders explored some of the vast territory, and Natchitoches (the oldest settlement within the present boundaries of the state of Louisiana) grew from a French military and trading post established (c.1714) to protect the Red River area from the Spanish.
In order to increase the value of the colony, France granted (1712) a monopoly of commercial privileges, which in 1717 passed to a company organized by John Law. The promise of riches under Law's Mississippi Scheme brought many settlers to Louisiana, and a large number of them remained even after his scheme had collapsed. New Orleans was founded in 1718, and in 1723 the capital was transferred there. Large numbers of Africans were brought in as slaves, and the Code Noir, adopted in 1724, provided for the rigid control of their lives and the protection of the whites.
The last conflict (1754–63) of the French and Indian Wars was ending disastrously for the French, and in order to keep the entire Louisiana territory from falling into the hands of the British, the French secretly ceded (by the Treaty of Fontainebleau in 1762) the area W of the Mississippi and the "Isle of Orleans" to Spain. By the Treaty of Paris (1763; see Paris, Treaty of), Great Britain gained control of all Louisiana E of the Mississippi except the "Isle of Orleans"; these changes were announced in 1764.
The French colonists resisted the new Spanish rule, but were subdued and finally Spanish mercantilistic monopoly of trade was instituted. During the Spanish years agriculture flourished with the cultivation of rice and sugarcane, and New Orleans grew as a major port and trading center. The Spanish government welcomed thousands of Acadians (see Acadia), known there as Cajuns, and they settled what came to be known as the Cajun country. During the American Revolution, New Orleans was a center for Spanish aid to the colonies. After Spain declared war on Great Britain in 1779, Louisiana's governor, Bernardo de Gálvez, became an active ally of the revolutionists, capturing Baton Rouge and Natchez (1779), Mobile (1780), and Pensacola (1781).
After the war Louisiana's control of the great inland trade route, the Mississippi, led to heated controversy with the Americans. In the secret Treaty of San Ildefonso (1800), Napoleon I forced the retrocession of the territory to France. Revelation of this treaty caused profound concern in the United States. President Jefferson attempted to purchase the "Isle of Orleans" from France. To the surprise of the American representatives in France, Napoleon decided to sell all of Louisiana to the United States (see Louisiana Purchase).
The United States took possession in 1803, and in 1804 the territory was divided into two parts. The southern part, which was called the Territory of Orleans, was admitted to the Union in 1812 as the state of Louisiana. In 1811 a brief slave uprising upriver from New Orleans was brutally crushed. Settlement (1819) of the West Florida Controversy gave Louisiana the area between the Mississippi and Pearl rivers, which formerly had been part of Florida. After statehood French and Spanish influence remained, not only in the Creole and Cajun societies but also in the civil law (based on French and Spanish codes) and in the division of the state into parishes rather than counties. In the early years of the 19th cent. the diverse people of Louisiana—the French, the Spanish, the Germans, and Isleños brought by Gálvez from the Canary Islands—united behind Andrew Jackson to defeat (1815) the British at the Battle of New Orleans during the War of 1812. (The battle site is contained in Jean Lafitte National Historical Park and Preserve; see National Parks and Monuments, table.)
With settlers pouring in from other Southern states, great sugar and cotton plantations developed rapidly in the fertile lowlands, and the less productive uplands were also settled. The state capital was moved several times, finally to Baton Rouge in 1849. The advent of steam propulsion on the Mississippi (the first steamboat to navigate the river arrived in New Orleans in 1812) was a boon to the state's economy; by 1840, New Orleans was the nation's second largest port. Plantation owners, with their large landholdings and many slaves (more than half the population) dominated politics and largely controlled the state.
On Jan. 26, 1861, Louisiana seceded from the Union and six weeks later joined the Confederacy. The fall of New Orleans to David G. Farragut in 1862 prefaced the detested military occupation under Gen. B. F. Butler. Occupied Louisiana was a proving ground for Lincoln's moderate restoration program, but after Lincoln's assassination radical Republicans seized control and Louisiana suffered greatly during Reconstruction. The Ku Klux Klan was particularly active from 1866 to 1871. In the election of 1872 the radical Republican candidate for governor lost but was installed with the help of federal troops. Reconstruction in Louisiana finally ended with the disputed presidential election of 1876, when Louisiana's electoral votes were "traded" to the Republicans (whose candidate was Rutherford B. Hayes) in exchange for the withdrawal of federal troops from the state. Francis R. T. Nicholls, a Democrat, became governor of Louisiana, and white control of the state was reestablished.
Economic recovery was slow. The disrupted plantation system was largely replaced by farm tenancy and sharecropping. The decline of steamboat traffic was offset somewhat by new railroad building and the opening of the Mississippi River for oceangoing vessels from New Orleans to the sea (a feat accomplished by James B. Eads). Mississippi floods constituted a serious problem, and levee building increased after the flood of 1882; it was only after the disastrous flood of 1927, however, that the federal government undertook a vast control system. The water resources development program encompasses flood control, navigation, drainage, and irrigation.
The pattern of Louisiana's economy was changed by the discovery of oil and natural gas in the early 1900s, and industries began to grow on the basis of cheap fuel and cheap labor. Medical advances helped to curb the yellow-fever epidemics that had periodically disrupted the state.
Industrial growth and the continuing woes of the tenant farmers did not alter control of the state by "Bourbon" Democrats, but in 1928 a virtual revolution occurred when Huey P. Long was elected governor. His almost dictatorial rule, detested by liberals across the nation, brought material progress at the cost of widespread official corruption. Long withstood all outside pressures, including the opposition of President F. D. Roosevelt's administration. After his assassination in 1935 (he had resigned the governorship in 1931 to become a U.S. Senator but had retained control over the state), his political heirs made their peace with the New Deal, and federal funds, withheld during Long's last years, poured into the state.
In 1948, Huey's brother, Earl Long, invoking the memory of his dead brother (still regarded by many as a savior and a martyr), gained the governorship. In addition, Huey's son Russell was elected to the U.S. Senate and served for 38 years until he retired in 1986. In 1956, Earl Long was again elected governor, but his second term was marked by scandal and controversy.
About one third of Louisianans are African American, and their struggle for civil rights has been long and bitter. The move toward integration following the 1954 Supreme Court ruling against racial segregation in public schools was difficult, and continuing resistance to social change is reflected in the careers of David Duke and others.
Hurricanes and flooding are recurrent dangers for the state. In 1965, Hurricane Betsy killed 74 and caused property damage in excess of $1 billion. In 1969, Hurricane Camille was even more destructive, ravaging Louisiana and neighboring states and killing 256 people. In Apr., 1973, the Mississippi River rose to its highest level recorded in Louisiana and, with its tributaries, flooded more than 10% of the state.
Louisiana enjoyed an oil boom in the early 1980s but then suffered following the 1986 collapse of oil prices. The state's unemployment rate rose to the highest in the nation, and economic distress grew. The slump placed a great burden on the tourist industry and led to increased efforts to diversify the economy. The state's recent environmental woes have largely arisen from the fact that natural erosion, oil exploitation, and river control projects have severely degraded its freshwater marshlands, especially in the delta of the Mississippi.
In 2005 Hurricanes Katrina and Rita devastated parts of the state, especially around New Orleans and along the Gulf Coast; as a result, it was estimated that some 240,000 people subsequently left Louisiana, largely from New Orleans, and the state and the city have only gradually regained those losses. A blowout of a deep offshore oil well in 2010 led to the largest oil spill in U.S. history and polluted portions of the state's E Gulf Coast, in most cases affecting areas that had been hit hard by Katrina.