Maps of Ohio tend to be an vital element of genealogy and family tree research, particularly in the event you live far from where your ancestor resided. Given that Ohio political borders sometimes changed, historic maps are generally essential in assisting you find out the exact location of your ancestor’s home, exactly what land they owned, just who their neighbors had been, and a lot more.
Maps of Ohio usually have a tendency to be an excellent resource for getting started with your research, since they provide you with significantly useful information and facts right away. Ohio Maps are usually a major resource of considerable amounts of details on family history.
Ohio borders Pennsylvania, West Virginia, Kentucky, Indiana and Michigan. Ohio’s 10 largest cities are Columbus, Cleveland, Cincinnati, Toledo, Akron, Dayton, Parma, Youngstown, Canton and Lorain.
Learn more about Historical Facts of Ohio Counties.
Interactive Map of Ohio County Formation History
List Of Every Ohio County
Adams County
Adams County was established on July 10, 1797, and its county seat is West Union. The county was named after John Adams, the second president of the United States. It has a population of 27,542 and covers an area of 583.91 square miles.
Allen County
Allen County was established on March 1, 1820, and its county seat is Lima. The county was named after John Allen, a War of 1812 colonel. It has a population of 101,670 and covers an area of 404.43 square miles.
Ashland County
Ashland County was established on February 24, 1846, and its county seat is Ashland. The county was formed from portions of Wayne, Richland, Huron, and Lorain counties. It was named after Ashland, the home of U.S. Senator from Kentucky Henry Clay. It has a population of 52,316 and covers an area of 424.37 square miles.
Ashtabula County
Ashtabula County was established on June 7, 1807, and its county seat is Jefferson. The county was formed from portions of Trumbull and Geauga counties. The county was named after the Ashtabula River, which means “fish river” in an Algonquian language. It has a population of 97,337 and covers an area of 702.44 square miles.
Athens County
Athens County was established on March 1, 1805, and was formed from Washington County. It was named after Athens in Greece. The county has a population of 62,056 and covers an area of 506.76 sq mi (1,313 km2).
Auglaize County
Auglaize County was established on February 14, 1848, and was formed from Allen, Mercer, Darke, Hardin, Logan, Shelby, and Van Wert Counties. It was named after the Auglaize River, which means “fallen timbers river” in the Shawnee Indian language. The county has a population of 46,141 and covers an area of 401.25 sq mi (1,039 km2).
Belmont County
Belmont County was established on September 7, 1801, and was formed from Jefferson and Washington Counties. It was named after the French for “beautiful mountain”. The county has a population of 65,849 and covers an area of 537.35 sq mi (1,392 km2).
Brown County
Brown County was established on March 1, 1818, and was formed from Adams and Clermont Counties. It was named after General Jacob Brown (1775–1828), an officer of the War of 1812. The county has a population of 43,662 and covers an area of 491.76 sq mi (1,274 km2).
Butler County
Butler County was established on May 1, 1803, and was formed from Hamilton County. It was named after General Richard Butler (1743–1791), who was killed at the Battle of the Wabash. The county has a population of 390,234 and covers an area of 467.27 sq mi (1,210 km2).
Carroll County
Carroll County was established on January 1, 1833, and was formed from Columbiana, Stark, Harrison, Jefferson, and Tuscarawas Counties. It was named after Charles Carroll (1737–1832), the last surviving signer of the United States Declaration of Independence. The county has a population of 26,691 and covers an area of 394.67 sq mi (1,022 km2).
Champaign County
Champaign County was established on March 1, 1805, and was formed from Greene and Franklin Counties. It was named after the French for “a plain”, describing the land in the area. The county has a population of 38,699 and covers an area of 428.56 sq mi (1,110 km2).
Clark County
Clark County was established on March 1, 1818, and was formed from Champaign, Madison, and Greene Counties. It was named after General George Rogers Clark (1752–1818), who defeated the Shawnee Indians in a battle near the Springfield area. The county has a population of 135,633 and covers an area of 399.86 sq mi (1,036 km2).
Clermont County
Clermont County was established on December 6, 1800, and was named after the French for “clear mountain.” Its county seat is Batavia. The county was formed from Hamilton County. As of the 2020 census, the population of Clermont County was 209,642, making it the 14th most populous county in Ohio. The county covers an area of 451.99 square miles (1,171 km2).
Crawford County
Crawford County was established on April 1, 1820, and was named after Colonel William Crawford, a Revolutionary War officer. The county seat is Bucyrus, and its population is 41,754. Crawford County has an area of 402.11 square miles (1,041 km2).
Cuyahoga County
Cuyahoga County
Cuyahoga County was founded on June 7, 1807, and is the second most populous county in Ohio. The county seat is Cleveland, which is also the largest city in the county. The name “Cuyahoga” comes from a Native American word meaning “crooked river.” Cuyahoga County has a population of 1,235,072 and covers an area of 1,245.90 square miles (3,224 km2).
Darke County
Darke County
Darke County was established on March 1, 1817, and was named after William Darke, a general in the American Revolutionary War. The county seat is Greenville, and its population is 50,205. Darke County has an area of 600.63 square miles (1,555 km2).
Defiance County
Defiance County
Defiance County was established on April 2, 1845, and was named after Fort Defiance, which was built near the confluence of the Auglaize River and the Maumee River during the War of 1812. The county seat is Defiance, and its population is 38,265. Defiance County has an area of 411.50 square miles (1,065 km2).
Delaware County
Delaware County
Delaware County was established on March 1, 1808, and was named after the Delaware tribe of Native Americans. The county seat is Delaware, and its population is 218,114. Delaware County has an area of 456.09 square miles (1,181 km2).
Erie County
Erie County was established on March 15, 1838. It was formed from Huron and Sandusky counties and named after the Erie Indians. The county seat of Erie County is Sandusky. With a population of 74,852 people and an area of 254.88 square miles, Erie County is home to Cedar Point, one of the world’s most famous amusement parks.
Fairfield County
Fairfield County was established on December 9, 1800. It was created from Ross and Washington counties and named for its “fair fields.” The county seat of Fairfield County is Lancaster. The county has a population of 161,064 and an area of 505.11 square miles.
Fayette County
Fayette County was established on March 1, 1810. It was formed from Ross and Highland counties and named after Gilbert du Motier, marquis de La Fayette, a French military officer who participated in both the American and French revolutions. The county seat of Fayette County is Washington Court House. Fayette County covers an area of 406.58 square miles and has a population of 28,906.
Franklin County
Franklin County was established on April 30, 1803. It was formed from Ross and Wayne counties and named after Benjamin Franklin, one of the Founding Fathers of the United States. The county seat of Franklin County is Columbus. Franklin County is the most populous county in Ohio, with a population of 1,321,414 people and an area of 539.87 square miles.
Fulton County
Fulton County was established on April 1, 1850. It was formed from Lucas, Henry, and Williams counties and named after Robert Fulton, the inventor of the steamboat. The county seat of Fulton County is Wauseon. Fulton County has a population of 42,450 and covers an area of 406.78 square miles.
Gallia County
Gallia County was established on April 30, 1803. It was created from Washington and Adams counties and named after Gaul, the ancient name of France. The county seat of Gallia County is Gallipolis. Gallia County has a population of 29,158 people and an area of 468.78 square miles.
Geauga County
Geauga County was established on March 1, 1806. It was formed from Trumbull County and named after an Indian word meaning “raccoon.” The county seat of Geauga County is Chardon. Geauga County has a population of 95,565 people and covers an area of 403.66 square miles.
Greene County
Greene County was established on May 1, 1803. It was formed from Hamilton and Ross counties and named after General Nathanael Greene, a Revolutionary War officer. The county seat of Greene County is Xenia. The county has a population of 168,412 and covers an area of 414.88 square miles.
Guernsey County
Guernsey County was established on March 1, 1810. It was created from Belmont and Muskingum counties and named after the Island of Guernsey, where most of the county’s settlers originated. The county seat of Guernsey County is Cambridge. The county has a population of 38,287 and covers an area of 521.90 square miles.
Hamilton County
Hamilton County was formed in 1790 as one of the original counties in the state of Ohio. It is named after Alexander Hamilton, who was the Secretary of the Treasury when the county was organized. With a population of 826,139 people and an area of 407.36 square miles (1,055 km2), it is the third most populous county in Ohio and home to the city of Cincinnati.
Hancock County
Hancock County was established on April 1, 1820, and named after John Hancock, the president of the Continental Congress. The county has an area of 531.35 square miles (1,376 km2) and a population of 74,656 people. The county seat is Findlay, and it is known for its natural gas and oil production.
Hardin County
Hardin County was founded on April 1, 1820, and named after John Hardin, a Revolutionary War officer. The county covers an area of 470.29 square miles (1,218 km2) and has a population of 30,621 people. Kenton is the county seat, and the county is known for its rich agricultural production.
Harrison County
Harrison County was created on February 1, 1813, and named after William Henry Harrison, an officer of the War of 1812 and future President of the United States. The county has an area of 403.53 square miles (1,045 km2) and a population of 14,477 people. The county seat is Cadiz, and it is home to several historic covered bridges.
Henry County
Henry County was established on April 1, 1820, and named after Patrick Henry, a Revolutionary War-era legislator, orator, and scholar. The county seat is Napoleon, and the county has a population of 27,538. Henry County covers an area of 416.50 square miles.
Highland County
Highland County was established on May 1, 1805, and named after its terrain. The county seat is Hillsboro, and the county has a population of 43,354. Highland County covers an area of 553.28 square miles.
Hocking County
Hocking County was established on March 1, 1818, and possibly derived its name from the Delaware Indian word “Hoch-Hoch-ing,” meaning “bottle.” The county seat is Logan, and the county has a population of 28,097. Hocking County covers an area of 422.75 square miles.
Holmes County
Holmes County was established on January 20, 1824, and named after Major Andrew Holmes, a War of 1812 officer. The county seat is Millersburg, and the county has a population of 44,271. Holmes County covers an area of 422.99 square miles.
Huron County
Huron County was established on March 7, 1809, and named after the Erie tribe of Native Americans who inhabited the area. The county seat is Norwalk, and the county has a population of 58,335. Huron County covers an area of 495.35 square miles.
Jackson County
Jackson County was established on March 1, 1816, and named after Andrew Jackson, a general during the War of 1812 and future President of the United States. The county seat is Jackson, and the county has a population of 32,302. Jackson County covers an area of 420.98 square miles.
Jefferson County
Jefferson County was founded in 1797 and named after Thomas Jefferson, who was the Vice President at that time and later became the President of the United States. The county has a population of 64,789 and covers an area of 409.61 square miles.
Knox County
Knox County was established in 1808 and was named after General Henry Knox, the first Secretary of War. It has a population of 62,897 and covers an area of 527.12 square miles.
Lake County
Lake County was founded in 1840 and was named after its location on Lake Erie. The county covers an area of 228.21 square miles and has a population of 232,023.
Lawrence County
Lawrence County was established in 1815 and was named after Captain James Lawrence, a naval hero in the War of 1812. The county has a population of 57,445 and covers an area of 454.96 square miles.
Licking County
Licking County was founded in 1808 and was named after the Licking River, which was named for the salt licks in the area. Alternatively, it was named after the English pronunciation of the Lenape word W’li/’ik’/nk meaning “where the flood waters recede.” The county has a population of 180,401 and covers an area of 686.50 square miles.
Logan County
Logan County was established in 1818 and was named after General Benjamin Logan, who destroyed Shawnee Indian towns in the county. The county has a population of 46,035 and covers an area of 458.44 square miles.
Lorain County
Lorain County was founded in 1822 and was named after the Province of Lorraine in France. The county covers an area of 492.50 square miles and has a population of 315,595.
Lucas County
Lucas County was established in 1835 and was named after Robert Lucas, who was the Governor of Ohio when the county was created. The county has a population of 429,191 and covers an area of 340.46 square miles.
Madison County
Madison County was founded in 1810 and was named after James Madison, the fourth President of the United States. The county covers an area of 465.44 square miles and has a population of 44,386.
Mahoning County
Mahoning County was established in 1846 and was named after the Mahoning River, which was named from a Lenape word meaning “at the licks.” The county has a population of 226,762 and covers an area of 415.25 square miles.
Marion County
Marion County was founded in 1820 and was named after General Francis Marion, who was a lieutenant colonel in the Continental Army and later a brigadier general in the American Revolutionary War. The county has a population of 65,291 and covers an area of 403.84 square miles.
Medina County
Medina County was established in 1812 and was named after the city of Medina, which is a world-renowned religious site in western Saudi Arabia. The county covers an area of 423 square miles and has a population of 183,092.
Meigs County
Meigs County was established in 1819, and it was named after Jonathan Meigs, Jr. who was the Governor of Ohio and Postmaster General at the time. The county was formed from portions of Gallia and Athens counties, and it has a population of 22,049 people. The total area of the county is 429.42 square miles, and it is located in the southeastern part of Ohio.
Mercer County
Mercer County was established in 1820, and it was named after General Hugh Mercer, who was a Revolutionary War officer. The county was formed from a portion of Darke County, and it has a population of 42,309 people. The total area of the county is 463.27 square miles, and it is located in the west-central part of Ohio.
Miami County
Miami County was established in 1807, and it was named after the Miami Indian tribe. The county was formed from Montgomery County, and it has a population of 109,264 people. The total area of the county is 407.04 square miles, and it is located in the west-central part of Ohio.
Monroe County
Monroe County was established in 1813, and it was named after James Monroe, who was the Secretary of State when the county was organized and future President of the United States. The county was formed from portions of Belmont, Washington, and Guernsey counties, and it has a population of 13,329 people. The total area of the county is 455.54 square miles, and it is located in the southeastern part of Ohio.
Montgomery County
Montgomery County was established in 1803, and it was named after General Richard Montgomery, who was a Revolutionary War officer. The county was formed from portions of Hamilton and Wayne counties, and it has a population of 535,840 people. The total area of the county is 461.68 square miles, and it is located in the west-central part of Ohio.
Morgan County
Morgan County was established in 1817, and it was named after General Daniel Morgan, who was a Revolutionary War officer. The county was formed from portions of Washington, Guernsey, and Muskingum counties, and it has a population of 13,682 people. The total area of the county is 417.66 square miles, and it is located in the southeastern part of Ohio.
Morrow County
Morrow County was established in 1848, and it was named after Jeremiah Morrow, who was the Governor of Ohio. The county was formed from portions of Knox, Marion, Delaware, and Richland counties, and it has a population of 35,151 people. The total area of the county is 406.22 square miles, and it is located in the north-central part of Ohio.
Muskingum County
Muskingum County was established in 1804, and it was formed from portions of Washington and Fairfield counties. The name of the county is derived from an Indian word meaning “A town by the river” or “by the river side”. The county has a population of 86,408 people, and the total area is 664.63 square miles. Muskingum County is located in the east-central part of Ohio.
Noble County
Noble County was founded in 1851 and was formed from parts of Monroe, Washington, Morgan, and Guernsey Counties. The county was named after James Noble, who was an early settler in the area. The county seat is Caldwell, and the county covers an area of 399.00 square miles. As of 2020, the estimated population of Noble County is 14,176.
Ottawa County
Ottawa County was established in 1840 and was created from portions of Erie, Sandusky, and Lucas Counties. The county was named after the Ottawa Indians, and the word “Ottawa” means “trader” in their language. The county seat is Port Clinton, and the county covers an area of 254.95 square miles. As of 2020, the estimated population of Ottawa County is 40,104.
Paulding County
Paulding County was founded in 1820 and was formed from parts of Darke County. The county was named after John Paulding, who was the captor of spy John André during the Revolutionary War. The county seat is Paulding, and the county covers an area of 416.26 square miles. As of 2020, the estimated population of Paulding County is 18,871.
Perry County
Perry County was established in 1818 and was created from parts of Washington, Fairfield, and Muskingum Counties. The county was named after Commodore Oliver Hazard Perry, who was a naval officer during the War of 1812. The county seat is New Lexington, and the county covers an area of 409.78 square miles. As of 2020, the estimated population of Perry County is 35,460.
Pickaway County
Pickaway County was founded in 1810 and was formed from parts of Ross, Fairfield, and Franklin Counties. The county was named after a misspelling of the Piqua tribe, which was a branch of the Shawnee. The county seat is Circleville, and the county covers an area of 501.91 square miles. As of 2020, the estimated population of Pickaway County is 59,333.
Pike County
Pike County was established in 1815 and was created from parts of Ross, Scioto, and Adams Counties. The county was named after General Zebulon M. Pike, who was a War of 1812 officer and discoverer of Pikes Peak in Colorado in 1806. The county seat is Waverly, and the county covers an area of 441.49 square miles. As of 2020, the estimated population of Pike County is 27,089.
Portage County
Portage County was founded in 1807 and was formed from parts of Trumbull County. The county’s name comes from the fact that it is located at a portage between the Cuyahoga and Tuscarawas Rivers. The county seat is Ravenna, and the county covers an area of 492.39 square miles. As of 2020, the estimated population of Portage County is 162,382.
Preble County
Preble County was established on March 1, 1808, from Montgomery and Butler counties. It was named after Captain Edward Preble, who was a Naval commander in the Revolutionary War. The county seat is Eaton, and its population is estimated to be 40,867, residing over an area of 424.80 square miles.
Putnam County
Putnam County was formed on April 1, 1820, from Shelby County. It was named after General Israel Putnam, who was a Revolutionary War officer. The county seat is Ottawa, and its population is estimated to be 34,318, residing over an area of 483.87 square miles.
Richland County
Richland County was established on March 1, 1808, from Fairfield County. It was named after the soil in the area, which was descriptive. The county seat is Mansfield, and its population is estimated to be 125,195, residing over an area of 496.88 square miles.
Ross County
Ross County was established on August 20, 1798, from Adams and Washington counties. It was named after U.S. Senator from Pennsylvania James Ross by territorial governor Arthur St. Clair. The county seat is Chillicothe, and its population is estimated to be 76,891, residing over an area of 688.41 square miles.
Sandusky County
Sandusky County was formed on April 1, 1820, from Huron County. It was named after an Iroquois word meaning “cold water”. The county seat is Fremont, and its population is estimated to be 58,715, residing over an area of 409.18 square miles.
Scioto County
Scioto County was established on May 1, 1803, from Adams County. It was named after the Scioto River, and “Scioto” is a Wyandot Indian word meaning “deer”. The county seat is Portsmouth, and its population is estimated to be 73,346, residing over an area of 612.27 square miles.
Seneca County
Seneca County was formed on April 1, 1820, from Huron County. It was named after the Seneca Indians, who had a reservation in the county area at the time. The county seat is Tiffin, and its population is estimated to be 54,906, residing over an area of 550.59 square miles.
Shelby County
Shelby County was established on April 1, 1819, from Miami County. It was named after General Isaac Shelby, who was a Revolutionary War officer and Governor of Kentucky. The county seat is Sidney, and its population is estimated to be 47,977, residing over an area of 409.27 square miles.
Stark County
Stark County was established on February 13, 1808, from Columbiana County. It was named after General John Stark, who was a Revolutionary War officer and known as the “Hero of Bennington” for his exemplary service at the Battle of Bennington in 1777. The county seat is Canton, and its population is estimated to be 373,834, residing over an area of 576.14 square miles.
Summit County
Summit County was established on March 3, 1840, from parts of Medina, Portage, and Stark Counties. Its name was inspired by its location, which is the highest elevation along the Ohio and Erie Canal. Summit County’s population is 537,633, and it covers an area of 419.38 sq mi (1,086 km2).
Trumbull County
Trumbull County was established on July 10, 1800, from parts of Jefferson and Wayne Counties. The county was named after Jonathan Trumbull, who was the Governor of Connecticut when the county was organized. Trumbull County’s population is 201,335, and it covers an area of 616.48 sq mi (1,597 km2).
Tuscarawas County
Tuscarawas County was established on March 15, 1808, from Muskingum County. The county was named after the Tuscarawas River, which means “open mouth river,” or the Tuscarawas tribe who lived on the river. Tuscarawas County’s population is 92,500, and it covers an area of 567.58 sq mi (1,470 km2).
Union County
Union County was established on April 1, 1820, from parts of Delaware, Franklin, Logan, and Madison Counties. The county was formed by a union of these four counties, hence the name. Union County’s population is 64,971, and it covers an area of 436.65 sq mi (1,131 km2).
Van Wert County
Van Wert County was established on April 1, 1820, from Darke County. The county was named after Isaac Van Wart, who was a captor of spy John André during the Revolutionary War. Van Wert County’s population is 28,732, and it covers an area of 410.09 sq mi (1,062 km2).
Vinton County
Vinton County was established on March 23, 1850, from parts of Athens, Gallia, Hocking, Jackson, and Ross Counties. The county was named after Samuel Finley Vinton, who was an Ohio Statesman and U.S. Congressman. Vinton County’s population is 12,696, and it covers an area of 414.08 sq mi (1,072 km2).
Warren County
Warren County was established on May 1, 1803, from Hamilton County. The county was named after General Joseph Warren, who was a Revolutionary War officer. Warren County’s population is 246,553, and it covers an area of 399.63 sq mi (1,035 km2).
Washington County
Washington County was established on July 27, 1788, and it was one of the original counties. The county was named after George Washington, who was a Revolutionary War officer, the president of the Constitutional Convention, and the future President of the United States. Washington County’s population is 59,423, and it covers an area of 635.15 sq mi (1,645 km2).
Wayne County
Wayne County was established on March 1, 1812, from Stark County. The county was named after General Anthony Wayne, who was a Revolutionary War officer. Wayne County’s population is 116,710, and it covers an area of 555.36 sq mi (1,438 km2).
Williams County
Williams County, established in 1820, was named after David Williams, who was the captor of spy John André during the Revolutionary War. The county seat is located in Bryan, and it has a population of 36,716 people. The county spans an area of 421.74 square miles and is highlighted on the state map.
Wood County
Wood County was refactored from non-county territory and established on April 1, 1820. The county was named after Eleazer D. Wood, the founder of Fort Meigs. The county seat is located in Bowling Green, and it has a population of 132,472 people. The county spans an area of 617.32 square miles and is highlighted on the state map.
Wyandot County
Wyandot County was established on February 3, 1845, and was formed from parts of Marion, Crawford, and Hardin counties. The county was named after the Wyandot Indians who once lived in the area. The county seat is located in Upper Sandusky, and it has a population of 21,708 people. The county spans an area of 405.61 square miles and is highlighted on the state map.
Old Antique Atlases & Maps of Ohio
- 1804 Ohio Atlas Map
- 1814 Atlas Map of Ohio
- 1822 Geographical, Historical, And Statistical Atlas Map Of Ohio
- 1827 Map of the States of Ohio, Ohio, & Illinois, and Part of the Michigan Territory
- 1836 A New Atlas Map Of Ohio with its Canals, Roads & Distances (with) Cincinnati
- 1845 Ohio Atlas Map
- 1856 Ohio Atlas Map. (with) Vicinity Of Cleveland Cuyahoga Co.
- 1856 City of Cincinnati
- 1866 State of Ohio
- 1880 County & township map of the states of Ohio and Ohio
- 1880 Plan of Cincinnati and vicinity
Ohio Map Links
- Ohio State Park Map (mapofus.org)
- Ohio Lakes and Rivers Map (mapofus.org)
- Ohio Map With Cities and Highways (mapofus.org)
- Ohio Digital Map Library (usgwarchives.net)
- Old Historical Maps of Ohio (alabamamaps.ua.edu)
- Ohio Maps, Atlases & Gazetteers (ancestry.com)
- U.S., Indexed Early Land Ownership and Township Plats, 1785-1898(search.ancestry.com)
- Ohio Maps – The Perry-Castañeda Library Map Collection (lib.utexas.edu)
- U.S., Indexed County Land Ownership Maps, 1860-1918 (ancestry.com)
- Ohio Map Books (amazon.com)