Delaware

New Castle

570,719
2020 population
1790
first census record
24
census records

About New Castle

New Castle, Delaware, first appears in the United States federal census in 1790, when it recorded a population of 19,688. At the most recent census, in 2020, its population stood at 570,719.

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

On the ground today, 11 documented military engagements have been recorded within the county, among them Battle of Brandywine — Chad's Ford, Battle of Cooch's Bridge (Delaware), Battle of Cooch's Bridge, and 418 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
2020570,719
2010538,479
2000500,265
1990441,946
1980398,115
1970385,856
1960307,446
1950218,879
1940179,562
1930161,032
1920148,239
1910123,188
1900109,697
189097,182
188077,716
187063,515
186054,797
185042,780
184033,120
183029,720
182027,899
181024,429
180025,361
179019,688
Source

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

Battles & engagements in New Castle

Military engagements that took place in New Castle, Delaware.

Battle of Brandywine — Chad's Ford
1777
Battle of Cooch's Bridge (Delaware)
1777
Battle of Cooch's Bridge
1777
Skirmish at Brandywine – Birmingham Hill
1777
Battle of Iron Hill
1777
Battle of Birmingham Hill (Brandywine)
1777
Battle of Brandywine — Birmingham Hill
1777
Christiana Bridge Skirmish
1777
Battle of Brandywine
1777
Battle of Cooch's Bridge (Delaware, 1777)
1777
Confederate Sabotage Delaware River
1864

Historic places in New Castle

National Register of Historic Places listings in New Castle, Delaware.

Morgan, William, Farm
Newark
Chambers House
Newark
Johnson Home Farm
Taylor's Bridge
Penn Farm of the Trustees of the New Castle Common
New Castle
Fort Delaware on Pea Patch Island
Delaware City
Graham, Robert, House
Newark
Carswell, Stuart Randall & Pricilla Kellogg, House
Newark
Odessa Historic District
Odessa
Mondamon Farm
Odessa
Brindley Farm
Wilmington
Pyle, Joshua, House and Wagon Barn
Wilmington
Weston
Middletown
Bancroft and Sons Cotton Mills
Wilmington
Center Meeting and Schoolhouse
Centerville
Public School No. 19
Wilmington
Old Fort Church
Christiana
Robinson House
Claymont
Wilmington Amtrak Station
Wilmington
Darley House
Claymont
Village of Arden
Wilmington
Lobdell Estate, Minquadale Home
Wilmington
Old First Presbyterian Church of Wilmington
Wilmington
Masonic Hall and Grand Theater
Wilmington
Torbert Street Livery Stables
Wilmington
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Other counties in Delaware

Explore census history and historic records for more Delaware counties.

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Everything a full report reveals about New Castle County, Delaware

This page charts the census history of New Castle County, Delaware. 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 New Castle

When does New Castle first appear in the US census?
New Castle, Delaware first appears in the federal census in 1790, with a recorded population of 19,688.
What is the population of New Castle?
At the most recent federal census (2020), New Castle had a recorded population of 570,719.
Were any battles fought in New Castle?
11 documented military engagements took place in New Castle, including Battle of Brandywine — Chad's Ford, Battle of Cooch's Bridge (Delaware), Battle of Cooch's Bridge.
How many historic places are in New Castle?
418 sites are listed on the National Register of Historic Places in New Castle, Delaware.
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