Jefferson County, Wisconsin

Jefferson County, Wisconsin
Jefferson County courthouse
Location in the U.S. state of Wisconsin
Wisconsin's location in the U.S.
Founded	1839
Named for	Jefferson County, New York
Seat	Jefferson
Largest city	Watertown
Area
• Total	583 sq mi (1,510 km2)
• Land	556 sq mi (1,440 km2)
• Water	26 sq mi (67 km2), 4.5%
Population
• (2010)	83,686
• Density	150/sq mi (58/km²)
Congressional district	5th
Time zone	Central: UTC-6/-5
Website	www.jeffersoncountywi.gov

Jefferson County is a county in the U.S. state of Wisconsin. As of the 2010 census, the population was 83,686. Its county seat is Jefferson.

Jefferson County comprises the Watertown-Fort Atkinson, WI Micropolitan Statistical Area, which is also included in the Milwaukee-Racine-Waukesha, WI Combined Statistical Area.

Jefferson County was created in 1836 as part of Wisconsin Territory and was organized in 1839. It was named after Jefferson County, New York, where some of the original settlers came from. The town of Watertown, Wisconsin was named after Watertown, New York in Jefferson County, New York.

According to the U.S. Census Bureau, the county has an area of 583 square miles (1,510 km²), of which 556 square miles (1,440 km²) is land and 26 square miles (67 km²) (4.5%) is water.

As of the census of 2010, there were 83,686 people, 32,117 households, and 21,872 families residing in the county. The population density was 133 people per square mile (51/km²). There were 30,092 housing units at an average density of 54 per square mile (21/km²). The county's racial makeup was 96.34% White, 0.28% Black or African American, 0.34% Native American, 0.45% Asian, 0.02% Pacific Islander, 1.65% from other races, and 0.93% from two or more races. 4.09% of the population were Hispanic or Latino of any race. 55.1% were of German, 6.1% Norwegian, 6.0% Irish and 5.1% American ancestry according to Census 2000.