Missouri

Clay

253,335
2020 population
1830
first census record
20
census records

About Clay

Clay, Missouri, first appears in the United States federal census in 1830, when it recorded a population of 5,338. At the most recent census, in 2020, its population stood at 253,335.

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

On the ground today, 10 documented military engagements have been recorded within the county, among them Battle of Blue Mills Landing, Liberty Skirmish (Clay County), Battle of Liberty, and 40 places are listed on the National Register of Historic Places.

Population by decade

Census YearPopulationChart
2020253,335
2010221,939
2000184,006
1990153,411
1980136,488
1970123,322
196087,474
195045,221
194030,417
193026,811
192020,455
191020,302
190018,903
189019,856
188015,572
187015,564
186013,023
185010,332
18408,282
18305,338
Source

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

Battles & engagements in Clay

Military engagements that took place in Clay, Missouri.

Battle of Blue Mills Landing
1861
Liberty Skirmish (Clay County)
1861
Battle of Liberty
1861
Clay County Guerrilla Raid (Quantrill)
1862
Liberty MO Skirmish (Clay County)
1862
Skirmish at Excelsior Springs, Missouri
1862
Watkins Mill Skirmish (Clay County)
1862
Excelsior Springs MO Skirmish (Ray County)
1863
Liberty MO Second Skirmish (Clay County, 1863)
1863
Skirmish at Liberty (Second), Missouri
1864

Historic places in Clay

National Register of Historic Places listings in Clay, Missouri.

Jewell Hall
Liberty
Compton, Dr. James, House
Kansas City
South Liberty Courthouse Square Historic District
Liberty
Clay County Savings Association Building
Liberty
James Brothers' House and Farm
Kearney
Watkins Mill
Excelsior
Major Hotel
Liberty
Excelsior Springs Hall of Waters Commercial East Historic District
Excelsior Springs
Downtown Smithville Historic District
Smithville
Clinton House
Liberty
Hughes, Frank, Memorial Library
Liberty
Excelsior Springs Hall of Waters Commercial West Historic District
Excelsior Springs
Hall of Waters
Excelsior Springs
Sears, Roebuck and Company Warehouse Building
North Kansas City
First Methodist Church
Excelsior Springs
IOOF Liberty Lodge No. 49
Liberty
Antioch Christian Church
Kansas City
Ligon Apartments
Excelsior Springs
Elms Hotel
Excelsior Springs
Wyman School
Excelsior Springs
Woodneath
Kansas City
Jewell-Lightburne Historic District
Liberty
Garrison School Historic District
Liberty
Dougherty-Prospect Heights Historic District
Liberty
Browse all Missourihistoric sites ›

Other counties in Missouri

Explore census history and historic records for more Missouri counties.

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Everything a full report reveals about Clay County, Missouri

This page charts the census history of Clay County, Missouri. 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 Clay

When does Clay first appear in the US census?
Clay, Missouri first appears in the federal census in 1830, with a recorded population of 5,338.
What is the population of Clay?
At the most recent federal census (2020), Clay had a recorded population of 253,335.
Were any battles fought in Clay?
10 documented military engagements took place in Clay, including Battle of Blue Mills Landing, Liberty Skirmish (Clay County), Battle of Liberty.
How many historic places are in Clay?
40 sites are listed on the National Register of Historic Places in Clay, Missouri.
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