Jefferson County may refer to one of several counties or parishes in the United States, all of which are named directly or indirectly after

Thomas Jefferson Thomas Jefferson (April 13, 1743 – July 4, 1826) was an American statesman, diplomat, lawyer, architect, philosopher, and Founding Fathers of the United States, Founding Father who served as the third president of the United States from 18 ...

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Jefferson County, Alabama Jefferson County is the List of counties in Alabama, most populous county in the U.S. state of Alabama, located in the central portion of the state. As of the 2020 United States census, 2020 census, its population was 674,721. Its county seat i ...

Jefferson County, Arkansas Jefferson County, Arkansas is a county located in the U.S. state of Arkansas in the area known as the Arkansas Delta that extends west of the Mississippi River. Jefferson County consists of five cities, two towns, and 20 townships. The county ...

Jefferson County, Colorado Jefferson County is a county located in the U.S. state of Colorado. As of the 2020 census, the population was 582,910, making it the fourth-most populous county in Colorado. The county seat is Golden, and the most populous city is Lakewood. ...

** Jefferson County, Jefferson Territory *

Jefferson County, Florida Jefferson County is a County (United States), county located in the Big Bend (Florida), Big Bend region in the North Florida, northern part of the U.S. state of Florida. As of the 2020 United States Census, 2020 census, the population was 14,510 ...

Jefferson County, Georgia Jefferson County is a county located in the U.S. state of Georgia. As of the 2020 census, the population was 15,709. The county seat is Louisville. The county was created on February 20, 1796, and named for Thomas Jefferson, the main author of ...

Jefferson County, Idaho Jefferson County is a county located in the U.S. state of Idaho. As of the 2020 Census, the county's population was 30,891. In the 2010 census, the population was 26,140. The county seat and largest city is Rigby. The county was established i ...

Jefferson County, Illinois Jefferson County is a county located in the southern part of the U.S. state of Illinois. According to the 2020 census, it has a population of 37,113. The county seat is Mount Vernon. Jefferson County contains the Mount Vernon, Illinois microp ...

Jefferson County, Indiana Jefferson County is a county located in the U.S. state of Indiana. As of 2020, the population was 33,147. The county seat is Madison. History Jefferson County was formed on February 1, 1811, from Dearborn and Clark Counties. It was named for ...

Jefferson County, Iowa Jefferson County is a county located in the U.S. state of Iowa. As of the 2020 United States Census, the population was 15,663. The county seat is Fairfield. The county was formed in January 1839, and was named for U.S. President Thomas Jeffers ...

Jefferson County, Kansas Jefferson County (county code JF) is a county located in the U.S. state of Kansas. At the 2020 census, the county population was 18,368. Its county seat is Oskaloosa, and its most populous city is Valley Falls. History Early history For ma ...

Jefferson County, Kentucky Jefferson County is located in the north central portion of the U.S. state of Kentucky. As of the 2020 census, the population was 782,969. It is the most populous county in the commonwealth (with more than twice the population of second ranked ...

Jefferson Parish, Louisiana Jefferson Parish (french: Paroisse de Jefferson; es, Parroquia de Jefferson) is a parish in the U.S. state of Louisiana. As of the 2020 census, the population was 440,781. Its parish seat is Gretna, its largest community is Metairie, and its ...

Jefferson County, Mississippi Jefferson County is a County (United States), county located in the U.S. state of Mississippi; its western border is formed by the Mississippi River. As of the 2010 United States Census, 2010 census, the population was 7,726, making it the third ...

Jefferson County, Missouri Jefferson County is located in the eastern portion of the state of Missouri. It is a part of the St. Louis Metropolitan Area. As of the 2020 census, the population was 226,739, making it the sixth-most populous county in Missouri. Its county s ...

Jefferson County, Montana Jefferson County is a county in Montana, United States. As of the 2020 census, the population was 12,085. Its county seat is Boulder. The county was created in 1865 and named for President Thomas Jefferson. Jefferson County is part of the Hel ...

Jefferson County, Nebraska Jefferson County is a county in the U.S. state of Nebraska. As of the 2020 United States Census, the population was 7,240. Its county seat is Fairbury. The county was named for Thomas Jefferson, third President of the United States of America. ...

Jefferson County, New York Jefferson County is a county on the northern border of the U.S. state of New York. As of the 2020 census, the population was 116,721. Its county seat is Watertown. The county is named after Thomas Jefferson, third President of the United Stat ...

Jefferson County, Ohio Jefferson County is a county located in the U.S. state of Ohio. As of the 2020 census, the population was 65,249. Its county seat is Steubenville. The county is named for Thomas Jefferson, who was vice president at the time of its creation. ...

Jefferson County, Oklahoma Jefferson County is a county located in the U.S. state of Oklahoma. As of the 2010 census, the population was 6,472. Its county seat is Waurika. The county was created at statehood and named in honor of President Thomas Jefferson.Jefferson County, Oregon Jefferson County is one of the 36 counties in the U.S. state of Oregon. At the 2020 census, the population was 24,502. The county seat is Madras. The county is named after Mount Jefferson. History Jefferson County was created on December 12, ...

Jefferson County, Pennsylvania Jefferson County is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 44,492. Its county seat is Brookville. The county was established on March 26, 1804, from part of Lycoming County and later organized ...

Jefferson County, Tennessee Jefferson County is an exurban County (United States), county located in the U.S. state of Tennessee. As of the 2020 United States census, 2020 census, the population was 54,683. Its county seat is Dandridge, Tennessee, Dandridge. Jefferson Coun ...

Jefferson County, Texas Jefferson County is a county in the Coastal Plain or Gulf Prairie region of Southeast Texas. The Neches River forms its northeast boundary. As of the 2020 census, the population was 256,526. The county seat is Beaumont. Jefferson County has t ...

Jefferson County, Virginia Jefferson County, Virginia has existed twice in the U.S. state of Virginia's history. Formed in 1780, and 1801, respectively, both County (United States), counties were named for one of that state's most celebrated residents, Thomas Jefferson, and ...

, has existed twice; the two counties continue in existence as Jefferson County, Kentucky and Jefferson County, West Virginia *

Jefferson County, Washington Jefferson County is a county located in the U.S. state of Washington. As of the 2020 census, the population was 32,977. The county seat and only incorporated city is Port Townsend. The county is named for Thomas Jefferson. Jefferson County wa ...

Jefferson County, West Virginia Jefferson County is located in the Shenandoah Valley in the Eastern Panhandle of West Virginia. It is the easternmost county of the U.S. state of West Virginia. As of the 2020 census, the population was 57,701. Its county seat is Charles Town ...

Jefferson County, Wisconsin Jefferson County is a county in the U.S. state of Wisconsin. As of the 2020 census, the population was 84,900. Its county seat is Jefferson. Jefferson County comprises the Watertown- Fort Atkinson, WI Micropolitan Statistical Area, which is a ...

See also