Sullivan County is the name of six counties in the United States of America:
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Sullivan County, Indiana
Sullivan County is a county in the U.S. state of Indiana, and determined by the US Census Bureau to include the mean center of U.S. population in 1940. As of 2023, the population was estimated at 20,757. The county seat (and the county's only ...
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Sullivan County, Missouri
Sullivan County is a county located in the northern portion of the U.S. state of Missouri. As of the 2020 census, the population was 5,999. Its county seat is Milan. The county was organized February 14, 1845, and named for Major General Joh ...
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Sullivan County, New Hampshire
Sullivan County is a County (United States), county in the U.S. state of New Hampshire. As of the 2020 United States census, 2020 census, the population was 43,063, making it the second-least populous county in New Hampshire. Its county seat i ...
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Sullivan County, New York
Sullivan County is a county in the U.S. state of New York. As of the 2020 census, the population was 78,624. The county seat is Monticello. The county's name honors Major General John Sullivan, who was labeled at the time as a hero in th ...
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Sullivan County, Pennsylvania
Sullivan County is a county in the Commonwealth of Pennsylvania. As of the 2020 census, the population was 5,840, making it the second-least populous county in Pennsylvania. Its county seat is Laporte. The county was created on March 15, 184 ...
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Sullivan County, Tennessee
Sullivan County is a county located in the U.S. state of Tennessee on its northeast border. As of the 2020 census, the population was 158,163. Its county seat is Blountville. Sullivan County is part of the Kingsport–Bristol TN-VA Metro ...
{{geodis, uscounty