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County Homepage |
Founded |
Parent County |
County Seat |
|
Adams |
1797 |
Hamilton |
West Union |
|
Allen |
1820 |
Shelby |
Lima |
|
Ashland |
1846 |
Wayne, Richland, Huron, Lorain |
Ashland |
|
Ashtabula |
1808 |
Trumbull, Geauga |
Jefferson |
|
Athens |
1805 |
Washington |
Athens |
|
Auglaize |
1848 |
Allen, Mercer, Darke, Hardin, Logan, Shelby, and Van Wert |
Wapakoneta |
|
Belmont |
1801 |
Jefferson, Washington |
Saint Clairsville |
|
Brown |
1818 |
Adams, Cleremont |
Georgetown |
|
Butler |
1803 |
Hamilton |
Hamilton |
|
Carroll |
1833 |
Columbiana, Stark, Harrison, Jefferson, Tuscarawas |
Carrollton |
|
Champaign |
1805 |
Green, Franklin |
Urbana |
|
Clark |
1818 |
Champaign, Madison, Greene |
Springfield |
|
Clermont |
1800 |
Hamilton |
Batavia |
|
Clinton |
1810 |
Highland, Warren |
Wilmington |
|
Columbiana |
1803 |
Jefferson, Washington |
Lisbon |
|
Coshocton |
1811 |
Muskingum, Tuscarawas |
Coshocton |
|
Crawford |
1820 |
Delaware |
Bucyrus |
|
Cuyahoga |
1808 |
Geauga |
Cleveland |
|
Darke |
1809 |
Miami |
Greenville |
|
Defiance |
1845 |
Williams, Henry, Paulding |
Defiance |
|
Delaware |
1808 |
Franklin |
Delaware |
|
Erie |
1838 |
Huron, Sandusky |
Sandusky |
|
Fairfield |
1800 |
Ross, Washington |
Lancaster |
|
Fayette |
1810 |
Ross, Highland |
Washington Court House |
|
Franklin |
1803 |
Ross, Wayne Co., MI |
Columbus |
|
Fulton |
1850 |
Lucas, Henry, Williams |
Wauseon |
|
Gallia |
1803 |
Washington, Adams |
Gallipolis |
|
Geauga |
1806 |
Trumbull |
Chardon |
|
Greene |
1803 |
Hamilton, Ross |
Xenia |
|
Guernsey |
1810 |
Belmont, Muskingum |
Cambridge |
|
Hamilton |
1790 |
Original County |
Cincinnati |
|
Hancock |
1820 |
Logan |
Findlay |
|
Hardin |
1820 |
Logan |
Kenton |
|
Harrison |
1813 |
Jefferson, Tuscarawas |
Cadiz |
|
Henry |
1820 |
Shelby |
Napoleon |
|
Highland |
1805 |
Ross, Adams, Clermont |
Hillsboro |
|
Hocking |
1818 |
Athens, Ross, Fairfield |
Logan |
|
Holmes |
1824 |
Coshocton, Wayne, Tuscarawas |
Millersburg |
|
Huron |
1815 |
Portage, Cuyahoga |
Norwalk |
|
Jackson |
1816 |
Scioto, Gallia, Athens, Ross |
Jackson |
|
Jefferson |
1797 |
Washington |
Steubenville |
|
Knox |
1808 |
Fairfield |
Mount Vernon |
|
Lake |
1840 |
Geauga, Cuyahoga |
Painesville |
|
Lawrence |
1815 |
Gallia, Scioto |
Ironton |
|
Licking |
1808 |
Fairfield |
Newark |
|
Logan |
1818 |
Champaign |
Bellefontaine |
|
Lorain |
1822 |
Huron, Cuyahoga, Medina |
Elyria |
|
Lucas |
1835 |
Wood, Sandusky, Huron |
Toledo |
|
Madison |
1810 |
Franklin |
London |
|
Mahoning |
1846 |
Columbiana, Trumbull |
Youngstown |
|
Marion |
1820 |
Delaware |
Marion |
|
Medina |
1812 |
Portage |
Medina |
|
Meigs |
1819 |
Gallia, Athens |
Pomeroy |
|
Mercer |
1820 |
Darke |
Celina |
|
Miami |
1807 |
Montgomery |
Troy |
|
Monroe |
1813 |
Belmont, Washington, Guernsey |
Woodsfield |
|
Montgomery |
1803 |
Hamilton, Wayne Co., MI |
Dayton |
|
Morgan |
1817 |
Washington, Guernsey, Muskingum |
McConnellsville |
|
Morrow |
1848 |
Knox, Marion, Delaware, Richland |
Mount Gilead |
|
Muskingum |
1804 |
Washington, Fairfield |
Zanesville |
|
Noble |
1851 |
Monroe, Washington, Morgan, Guernsey |
Caldwell |
|
Ottawa |
1840 |
Erie, Sandusky, Lucas |
Port Clinton |
|
Paulding |
1820 |
Darke |
Paulding |
|
Perry |
1818 |
Washington, Fairfield, Muskingum |
New Lexington |
|
Pickaway |
1810 |
Ross, Fairfield, Franklin |
Circleville |
|
Pike |
1815 |
Ross, Scioto, Adams |
Waverly |
|
Portage |
1808 |
Trumbull |
Ravenna |
|
Preble |
1808 |
Montgomery, Butler |
Eaton |
|
Putnam |
1820 |
Shelby |
Ottawa |
|
Richland |
1808 |
Fairfield |
Mansfield |
|
Ross |
1798 |
Adams, Washington |
Chillicothe |
|
Sandusky |
1820 |
Huron |
Fremont |
|
Scioto |
1803 |
Adams |
Portsmouth |
|
Seneca |
1820 |
Huron |
Tiffin |
|
Shelby |
1819 |
Miami |
Sidney |
|
Stark |
1808 |
Columbiana |
Canton |
|
Summit |
1840 |
|
Akron |
|
Trumbull |
1800 |
|
Warren |
|
Tuscarawas |
1808 |
Muskingum |
New Philadelphia |
|
Union |
1820 |
Franklin, Madison, Logan, Delaware |
Marysville |
|
Van Wert |
1820 |
Darke |
Van Wert |
|
Vinton |
1850 |
Gallia, Athens, Ross, Jackson, Hocking |
Mc Arthur |
|
Warren |
1803 |
Hamilton |
Lebanon |
|
Washington |
1788 |
Original County |
Marietta |
|
Wayne |
1808 |
Columbiana |
Wooster |
|
Williams |
1820 |
Darke |
Bryan |
|
Wood |
1820 |
Indian Lands |
Bowling Green |
|
Wyandot |
1845 |
Marion, Crawford, Hardin |
Upper Sandusky |