New York

Nassau

1,395,774
2020 population
1900
first census record
13
census records

About Nassau

Nassau, New York, first appears in the United States federal census in 1900, when it recorded a population of 55,448. At the most recent census, in 2020, its population stood at 1,395,774.

Its recorded population peaked at 1,428,080 in 1970, and has since declined by roughly 2 percent.

On the ground today, one documented military engagement has been recorded within the county, among them German Saboteur Landing (Long Island), and 156 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
20201,395,774
20101,339,532
20001,334,544
19901,287,348
19801,321,582
19701,428,080
19601,300,171
1950672,765
1940406,748
1930303,053
1920126,120
191083,930
190055,448
Source

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

Battles & engagements in Nassau

Military engagements that took place in Nassau, New York.

German Saboteur Landing (Long Island)
1942

Historic places in Nassau

National Register of Historic Places listings in Nassau, New York.

Seawanhaka Corinthian Yacht Club
Oyster Bay
Barkin House
Long Beach
Woolworth Estate
Glen Cove
US Post Office-Great Neck
Great Neck Plaza
Sands-Willets Homestead
Port Washington
Denton, George W., House
Flower Hill
Cedarmere-Clayton Estates
Roslyn Harbor
Mackay Estate Gate Lodge
East Hills
House at 103 Roslyn Avenue
Sea Cliff
US Post Office-Garden City
Garden City
Grace and Thomaston Buildings (Additional Documentation)
Great Neck Plaza
Roslyn Village Historic District
Roslyn
Cock-Cornelius House
Locust Valley
Titus, Willet, House
Roslyn
First Presbyterian Church of Oyster Bay
Oyster Bay
Fort Massapeag Archeological Site
Oyster Bay
Glen Cove Post Office
Glen Cove
Harding, Stephen, House
Sea Cliff
House at 240 Sea Cliff Avenue
Sea Cliff
Landsberg, William, House
Port Washington
North Hempstead Town Hall
Manhasset
Raynham Hall
Oyster Bay
St. George's Church
Hempstead
Goodyear, A. Conger, House
Old Westbury
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Everything a full report reveals about Nassau County, New York

This page charts the census history of Nassau County, New York. 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 Nassau

When does Nassau first appear in the US census?
Nassau, New York first appears in the federal census in 1900, with a recorded population of 55,448.
What is the population of Nassau?
At the most recent federal census (2020), Nassau had a recorded population of 1,395,774.
When did Nassau's population peak?
Nassau's recorded population peaked at 1,428,080 in 1970.
Were any battles fought in Nassau?
1 documented military engagement took place in Nassau, including German Saboteur Landing (Long Island).
How many historic places are in Nassau?
156 sites are listed on the National Register of Historic Places in Nassau, New York.
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