Ohio

Delaware

214,124
2020 population
1810
first census record
22
census records

About Delaware

Delaware, Ohio, first appears in the United States federal census in 1810, when it recorded a population of 2,000. At the most recent census, in 2020, its population stood at 214,124.

The county's recorded population has risen across the decades to its highest level in 2020.

On the ground today, 60 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
2020214,124
2010174,214
2000109,989
199066,929
198053,840
197042,908
196036,107
195030,278
194026,780
193026,016
192026,013
191027,182
190026,401
189027,189
188027,381
187025,175
186023,902
185021,817
184022,060
183011,504
18207,639
18102,000
Source

Population data from the United States decennial census, U.S. Census Bureau (public domain).

Historic places in Delaware

National Register of Historic Places listings in Delaware, Ohio.

Selby Field
Delaware
Ufferman Site
Delaware
Stratford Methodist Episcopal Church
Delaware
Delaware County Courthouse
Delaware
Highbank Park Works
Worthington
Delaware Public Library
Delaware
O'Shaughnessy Dam and Bridge
Shawnee Hills
Curtiss, Marcus, Inn
Galena
Highbanks Metropolitan Park Mounds I and II
Powell
Gooding House and Tavern
Orange Township
Delaware Post Office
Delaware
St. Mary's Church and Rectory
Delaware
Edwards Gymnasium/Pfieffer Natatorium
Delaware
Browse all Ohiohistoric sites ›

Other counties in Ohio

Explore census history and historic records for more Ohio counties.

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Everything a full report reveals about Delaware County, Ohio

This page charts the census history of Delaware County, Ohio. A full Aubrey report for an address here pulls together everything the historical record holds about the ground, from the earliest settlement to the twentieth century:

Overview
An interactive map of the location with historic sites, battles and Native heritage plotted, and its full story era by era.
The Land
The historic sites and place names around the location, and how this land was settled and used.
Geology
The bedrock beneath the site, its age and rock type, reaching back millions of years.
LiDAR Terrain
Laser-scanned terrain that reveals earthworks and old features hidden in the landscape.
Conflict & War
The battles, raids and skirmishes fought near here, across every era of American conflict.
The Civil War
The Civil War on this ground, 1861 to 1865: who held it, and the battles, camps and regiments nearby.
The Soldiers
The men who marched from here in the Civil War, named and traced where the record allows.
Native Heritage
The Native nations who held this land, mapped across time from before European contact to today.
Settlement
Who claimed and held this ground, from Indigenous homelands through the colonial powers to the United States.
The Community
How the town grew, who came, and what kind of place it became, traced through the census record.
Rivers & Rail
The rivers, canals and railroads that connected this place between 1830 and 1911.
Notable People
The people born, buried or genuinely tied to this exact place, with their stories.
Historical Maps
Historic maps of the location layered over how it looks today.
Finds & Access
Museum objects tied to the area, and the laws on searching, collecting and access here.
Literature
The old books, county histories and archives that mention this place, quoted with their sources.
Spotlight
A deep dive into the most remarkable, lesser-known history of the place, traced back to the record.
Points of Interest
The most significant historic sites and landmarks near the location, and why they matter.
Timeline
The whole story of the location told era by era, from first peoples to the present day.
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Frequently asked about Delaware

When does Delaware first appear in the US census?
Delaware, Ohio first appears in the federal census in 1810, with a recorded population of 2,000.
What is the population of Delaware?
At the most recent federal census (2020), Delaware had a recorded population of 214,124.
How many historic places are in Delaware?
60 sites are listed on the National Register of Historic Places in Delaware, Ohio.
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