What Indigenous territories am I in?

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, making it the fourth-least populous county in Mississippi. Its first county seat was located at Old Greenville until 1825, which no longer exists, before moving to Fayette. The county is named for U.S. President Thomas Jefferson. 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. 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.