| County: | Jefferson County |
| State: | Mississippi |
| Ex Image: | Christ Church, Church Hill, Mississippi.jpg |
| Ex Image Size: | 220px |
| Ex Image Cap: | Historic Christ Church, Church Hill, Mississippi. |
| Founded: | 1799 |
| Seat Wl: | Fayette |
| Largest City Wl: | Fayette |
| Area Total Sq Mi: | 527 |
| Area Land Sq Mi: | 520 |
| Area Water Sq Mi: | 7.3 |
| Area Percentage: | 1.4 |
| Population As Of: | 2020 |
| Population Total: | 7260 |
| Population Density Sq Mi: | auto |
| Web: | http://www.jeffersoncountyms.com/ |
| District: | 2nd |
| Time Zone: | Central |
| Named For: | Thomas Jefferson |
Jefferson County is a county located in the U.S. state of Mississippi; its western border is formed by the Mississippi River. As of the 2020 census, the population was 7,260,[1] making it the fourth-least populous county in Mississippi. Its first county seat was located at Old Greenville until 1825, which no longer exists,[2] before moving to Fayette.[3] The county is named for U.S. President Thomas Jefferson.[4]
One of the first of two counties organized in the Mississippi Territory in 1798 along with Adams County, it was first named Pickering County and included what would become Claiborne County.[5] Originally developed as cotton plantations in the antebellum era, the rural county has struggled with a declining economy and reduced population since the mechanization of agriculture and urbanization of other areas. In 2020, its population of 7,260 was roughly one-third of the population peak in 1900. Within the United States, in 2009 rural Jefferson County had the highest percentage of African-Americans of any county. It was the fourth-poorest county in the nation.[6]
According to the U.S. Census Bureau, the county has a total area of, of which is land and (1.4%) is water.[7]
| White | 891 | 12.27% | |
| Black or African American | 6,138 | 84.55% | |
| Native American | 10 | 0.14% | |
| Asian | 14 | 0.19% | |
| Pacific Islander | 5 | 0.07% | |
| Other/Mixed | 128 | 1.76% | |
| Hispanic or Latino | 74 | 1.02% |
Jefferson County School District operates public schools in all of the county.[9]
Jefferson County is overwhelmingly Democratic, and has supported Democratic candidates in presidential elections with at least 80% of the vote since Bill Clinton in 1992, who won 79%. Republicans have not garnered even 25% of the vote in presidential elections since 1972 (when Jefferson was one of only three counties in Mississippi to vote for George McGovern).
The last Republican to win the county was Barry Goldwater. Although Goldwater lost nationally in a landslide, he carried the state of Mississippi (and also Jefferson County) in a landslide, winning over 87% of the vote and carrying every county. Jefferson County supported him with 95% of the vote. Goldwater's lopsided victory was the result of Mississippi's decades-long suppression of the voting rights of African Americans, which only began to be reversed with the passage of the Voting Rights Act of 1965.