Iowa

Decatur

7,645
2020 population
1850
first census record
18
census records

About Decatur

Decatur, Iowa, first appears in the United States federal census in 1850, when it recorded a population of 965. At the most recent census, in 2020, its population stood at 7,645.

Its recorded population peaked at 18,115 in 1900, and has since declined by roughly 58 percent.

On the ground today, 7 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
20207,645
20108,457
20008,689
19908,338
19809,794
19709,737
196010,539
195012,601
194014,012
193014,903
192016,566
191016,347
190018,115
189015,643
188015,336
187012,018
18608,677
1850965
Source

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

Historic places in Decatur

National Register of Historic Places listings in Decatur, Iowa.

Grand River Bridge
Leon
Stearns, C. S., House
Garden Grove
Union Church
Davis City
Liberty Hall
Lamoni
McClung, J. J., House
Garden Grove
Missouri, Iowa & Nebraska Railway Co. Depot-Weldon
Weldon
Decatur County Courthouse
Leon

Other counties in Iowa

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Everything a full report reveals about Decatur County, Iowa

This page charts the census history of Decatur County, Iowa. 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 Decatur

When does Decatur first appear in the US census?
Decatur, Iowa first appears in the federal census in 1850, with a recorded population of 965.
What is the population of Decatur?
At the most recent federal census (2020), Decatur had a recorded population of 7,645.
When did Decatur's population peak?
Decatur's recorded population peaked at 18,115 in 1900.
How many historic places are in Decatur?
7 sites are listed on the National Register of Historic Places in Decatur, Iowa.
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