Iowa

Clayton

17,043

2020 population

1840

first census record

census records

About Clayton

Clayton, Iowa, first appears in the United States federal census in 1840, when it recorded a population of 1,101. At the most recent census, in 2020, its population stood at 17,043.

Its recorded population peaked at 28,829 in 1880, and has since declined by roughly 41 percent.

On the ground today, 63 places are listed on the National Register of Historic Places.

Population by decade

Census Year	Population	Chart
2020	17,043
2010	18,129
2000	18,678
1990	19,054
1980	21,098
1970	20,606
1960	21,962
1950	22,522
1940	24,334
1930	24,559
1920	25,032
1910	25,576
1900	27,750
1890	26,733
1880	28,829
1870	27,771
1860	20,728
1850	3,873
1840	1,101

Source

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

Historic places in Clayton

National Register of Historic Places listings in Clayton, Iowa.

St. Joseph Church and Parish Hall

Mallory Township Bridge

Osterdock

Garnavillo Township Culvert

Garnavillo

St. Mary's Catholic Church Historic District

Round Barn, Millville Township

St. Peters United Evangelical Lutheran Church

Ceres

Elkader Keystone Bridge

Elkader

First Congregational Church

Garnavillo

Stemmer, J. C., House

Elkader

Clayton School

Clayton

Davis, Timothy, House

Browse all Iowahistoric sites ›

Other counties in Iowa

Explore census history and historic records for more Iowa counties.

Washington Wayne Webster Winnebago Winneshiek Woodbury Worth Wright Adair Adams Allamakee Appanoose Audubon Benton Black Hawk Boone Bremer Buchanan Buena Vista Butler

Unlimited access

Everything a full report reveals about Clayton County, Iowa

This page charts the census history of Clayton 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.

First month just $5.99, then $11.99 a month. Unlimited locations, cancel anytime.

Every location is different. Not every section appears for every place, only what the historical record actually holds turns up in a report.

Start your Clayton County, Iowa report

Or see a real report first

Explore Iowa records

Iowahistory ›NRHP historic sites ›Notable people from Iowa›

Frequently asked about Clayton

When does Clayton first appear in the US census?

Clayton, Iowa first appears in the federal census in 1840, with a recorded population of 1,101.

What is the population of Clayton?

At the most recent federal census (2020), Clayton had a recorded population of 17,043.

When did Clayton's population peak?

Clayton's recorded population peaked at 28,829 in 1880.

How many historic places are in Clayton?

63 sites are listed on the National Register of Historic Places in Clayton, Iowa.

Aubrey Research

Research the history of any US location

Aubrey searches federal archives, archaeological records, historic registers, and primary sources to build a full historical report for any address or place in the United States.

Research your location View a free sample report