Waterloo Historic District
Why it's listed
Waterloo's historic district takes in most of the central part of the Monroe County seat, south of St. Louis, Illinois. It contains 271 structures arranged around a courthouse square, where commercial activity concentrated along the west side of Main Street while the other sides developed as housing. Sixteen buildings form a continuous wall on that side of Main, and only two date from the 20th century. Architecturally the district mixes long-lived Federal elements with Greek Revival, Italianate and Second Empire touches. Its most distinctive feature is the "German Street House," a small, usually brick cottage type built from before 1852 to at least 1901. These cottages recall the German immigrants who drove the town's growth after about 1840. The town was laid out in 1818 by George Forquer and Daniel Pope Cook and became the county seat in 1825. The nomination warns that aluminum siding, poor remodeling and suburban pressure from St. Louis threaten its integrity.
Significance in brief: The nomination argues the district is one of the most intact, if somewhat atypical, examples of a small 19th-century Illinois county seat. Its significance rests on the courthouse square, the nearly unbroken commercial front on Main Street, and the many small "German Street House" cottages that reflect German immigration. It also notes Waterloo's founders were prominent in early Illinois statehood.
Machine-generated summary. This summary was generated by a language model from the official nomination document and has not been reviewed line by line by an editor. It may contain errors. Check the source document before relying on any detail. Source: nomination document (PDF) · National Archives catalog entry. NRHP reference 78001177, listed December 1, 1978. Summary generated October 2026 (model claude-sonnet-5-5, prompt v1.0-2026-10-29, confidence medium).
Key facts
| Address | 517 S. Main St., Waterloo |
|---|---|
| County | Monroe County |
| Listed | December 1, 1978 |
| Reference number | 78001177 |
| Resource type | District |
| Period of significance | 1800-1899 |
| Architectural style | Federal, Greek Revival, Italianate and Second Empire elements, with the local "German Street House" cottage type |
| Areas of significance | Architecture |
| Level of significance | State |
| Status (as stated in the nomination) | Condition marked good. The area is mostly occupied and in use as commercial, governmental and residential space. About 40% of older background buildings have been resided, and 5.5% of structures are intrusive. |
| Acreage | 77 |
| Coordinates | 38.33518, -90.15218 (NPS GIS) |
What listing means for this property
This is a historic district. Buildings within its boundary are either contributing (they add to the district's significance) or non-contributing. Owners of contributing income-producing buildings can claim the 20% federal rehabilitation tax credit; homeowners should look at state credits. National Register districts impose no design review by themselves; a local historic district ordinance, if one exists, does (the difference explained).
General information, not legal or tax advice. Rules change; confirm with your State Historic Preservation Office or a qualified adviser.
Sources and further reading
- National Park Service, National Register of Historic Places database (snapshot May 2026), reference 78001177.
- Nomination form (PDF, National Archives) — catalog entry
- Wikipedia article (used for cross-checking only; text not reproduced here)
- Wikidata Q7974243
- This listing as JSON
Last updated October 2026. Found an error? See the editorial policy for how to report it.