Clay County, Iowa
county in Iowa, United States
Clay County is a county located in the U.S. state of Iowa. As of the 2020 census, the population was 16,384. Its county seat is Spencer. Its name is in honor of Henry Clay Jr., a colonel who died in action in the Mexican–American War, and son of Henry Clay, famous American statesman from Kentucky. Clay County comprises the Spencer, IA Micropolitan Statistical Area. Clay County holds the annual Clay County Fair. The first newspaper in Clay County was the Peterson Patriot which started publication in 1880.
Geography
According to the United States Census Bureau, the county has a total area of 573 square miles (1,480 km2), of which 567 square miles (1,470 km2) is land and 5.4 square miles (14 km2) (0.9%) is water. Clay County is home to the large Barringer Slough wetland.
Major highways
U.S. Highway 18
U.S. Highway 71
Iowa Highway 10
Airport
The Spencer Municipal Airport is located three miles (4.8 km) northwest of the business district of Spencer.
Begin with the source’s own compact description: “Clay County, Iowa” is county in Iowa, United States. The dossier treats that line as a proposition to test through Clay, County and Iowa, not as a finished interpretation.
Why this record matters
The phrase “county in Iowa, United States” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The strongest evidence will usually combine a dated visual record with documents produced by the authority responsible for the place. The source revision retrieved here is dated Sep 16, 2026. The linked authority identifier is Q156488. VIAF identifies the subject as 143074335. The Library of Congress control number is n81035042. Authority coordinates are 43.081, -95.149. 4 of 5 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 2020 and 1880.
Modern boundaries and familiar names can conceal earlier jurisdictions or structures that do not align with the present site. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Treat names, boundaries and functions as historically changeable. Maps, plans, inventories and administrative records can clarify what the place meant at different dates.
- Historic place names
- Jurisdictional context
- Routes into maps and plans
Contemporary maps, plans, listed-building records, estate papers and the responsible local or national archive.
Three-step research path
- Establish the record: confirm the title “Clay County, Iowa”, its source revision and the description used here.
- Expand the search: follow Clay County, Iowa primary sources, Clay County, Iowa archive and Clay research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Clay County, Iowa”?
- Which earlier names or jurisdictions may reveal additional records?
- Which authority defined the place, boundary or structure at the relevant date?
Search terms from this dossier
This entry incorporates text from “Clay County, Iowa” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.