Mississippi is a state located in the southern region of the United States of America. The state takes its name from the Mississippi River, which flows along its western boundary. The name Mississippi, which means "great river," comes from either Ojibwe, a Native American language spoken around the river's headwaters, or some other closely related Algonquian language (c.f. Ojibwe misi-ziibi). Nicknames for Mississippi are the Magnolia State and the Hospitality State.

Mississippi was part of the Mississippian culture in the early part of the 2nd millennium AD; descendant Native American tribes include the Chickasaw and Choctaw. Other tribes who inhabited the territory of Mississippi (and whose names became those of local towns) include the Natchez, the Yazoo, and the Biloxi.

The first European expedition into the territory that became Mississippi was that of Hernando de Soto, who passed through in 1540. The first settlement was Fort Maurepas (or Old Biloxi) at Ocean Springs, settled by Pierre Le Moyne d'Iberville in April 1699. In 1716, Natchez was founded on the Mississippi River (as Fort Rosalie); it became the dominant town and trading post of the area. After spending some time under Spanish, British, and French nominal jurisdiction, the Mississippi area was deeded to the British after the French and Indian War under the terms of the Treaty of Paris (1763).

The Mississippi Territory was organized on April 7, 1798, from territory ceded by Georgia and South Carolina; it was later twice expanded to include disputed territory claimed by both the U.S. and Spain. Land was purchased (generally through unequal treaties) from Native American tribes from 1800 to about 1830. Mississippi was the 20th state admitted to the Union, on December 10, 1817.

When cotton was king during the 1850s, Mississippi plantation owners—especially those of the Delta and Black Belt regions—became increasingly wealthy due to the high fertility of the soil and the high price of cotton on the international market. The severe wealth imbalances and the necessity of large-scale slave populations to sustain such income played a heavy role in both state politics and in the support for secession.

Mississippi was the second state to secede from the Union as one of the Confederate States of America on January 9, 1861. During the Civil War the Confederate States were defeated. Under the terms of Reconstruction, Mississippi was readmitted to the Union on February 23, 1870.

Mississippi was considered to typify the Deep South during the era of Jim Crow. A series of increasingly restrictive racial segregation laws enacted during the first part of the 20th century resulted in the emigration of almost half a million people, three-quarters of them black, in the 1940s. However, at the same time, Mississippi became a center of rich, quintessentially American music traditions: gospel music, country music, jazz, blues, and rock and roll all were invented, promulgated, or heavily developed by Mississippi musicians. Mississippi was also noted for its authors in the early twentieth century, especially William Faulkner and Tennessee Williams.

Mississippi was a focus of the American Civil Rights Movement. Through the actions and attitudes of many white politicians (Including the creation of the Mississippi State Sovereignty Commission), the involvement of many Mississippians in the White Citizens' Council movement, and the violent tactics of the Ku Klux Klan and its sympathizers, Mississippi gained a reputation in the 1960s as a reactionary state.

The state was the last to repeal prohibition (in 1966). It symbolically adopted the Thirteenth Amendment, which abolished slavery, in 1995. These amendments were still in effect in Mississippi even before their ratification there.

On August 17, 1969, Category 5 Hurricane Camille hit the Mississippi coast, killing 248 people and causing US$1.5 billion in damage (1969 dollars). On August 29, 2005, Hurricane Katrina, though a Category 3 storm upon final landfall, caused even greater destruction across the entire 90 miles of Mississippi Gulf Coast from Louisiana to Alabama.

On August 30, 2007, a report by the Census Bureau indicated that Mississippi is the poorest state in the country. The state had a median household income of $34,473.