Pennsylvania

Union

42,681
2020 population
1820
first census record
21
census records

About Union

Union, Pennsylvania, first appears in the United States federal census in 1820, when it recorded a population of 18,619. At the most recent census, in 2020, its population stood at 42,681.

Its recorded population peaked at 44,947 in 2010, and has since declined by roughly 5 percent.

On the ground today, one documented military engagement has been recorded within the county, among them Battle at Penn's Creek, and 18 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
202042,681
201044,947
200041,624
199036,176
198032,870
197028,603
196025,646
195023,150
194020,247
193017,468
192015,850
191016,249
190017,592
189017,820
188016,905
187015,565
186014,145
185026,083
184022,787
183020,795
182018,619
Source

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

Battles & engagements in Union

Military engagements that took place in Union, Pennsylvania.

Battle at Penn's Creek
1755

Historic places in Union

National Register of Historic Places listings in Union, Pennsylvania.

New Berlin Presbyterian Church
New Berlin
Reading Railroad Freight Station
Lewisburg
Lewisburg Armory
Lewisburg
Buffalo Presbyterian Church
Lewisburg
Chamberlin Iron Front Building
Lewisburg
Old Union County Courthouse
New Berlin
Heiss, William A., House and Buggy Shop
Mifflinburg
Lewisburg Historic District
Lewisburg
Slifer House
Lewisburg
Packwood House-American Hotel
Lewisburg
Hassenplug Bridge
Mifflinburg
Browse all Pennsylvaniahistoric sites ›

Other counties in Pennsylvania

Explore census history and historic records for more Pennsylvania counties.

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Everything a full report reveals about Union County, Pennsylvania

This page charts the census history of Union County, Pennsylvania. 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 Union

When does Union first appear in the US census?
Union, Pennsylvania first appears in the federal census in 1820, with a recorded population of 18,619.
What is the population of Union?
At the most recent federal census (2020), Union had a recorded population of 42,681.
When did Union's population peak?
Union's recorded population peaked at 44,947 in 2010.
Were any battles fought in Union?
1 documented military engagement took place in Union, including Battle at Penn's Creek.
How many historic places are in Union?
18 sites are listed on the National Register of Historic Places in Union, Pennsylvania.
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