Founding year: the first Spring Bay Township post office (Blevins & Helbock, CC0).
History grade
What drives Spring Bay Township’s History grade
On its age, its old homes and the National Register, Spring Bay Township is more historic than 50% of U.S. towns, #404 of 768 in Illinois. Its age holds the grade up; its National Register listings pull it down.
B−
HistoryA character grade: shown, never part of Spring Bay Township’s overall grade.
Few Illinois towns list much on the Register (a typical Illinois town has 0.5 per 10,000 residents, the U.S. 2.4), so Spring Bay Township’s 0.0 sits below most of its state (28% of Illinois towns have fewer) while its 0 listings outnumber those of 23% of U.S. towns.
How sure. Graded on any two of the three inputs instead, the letter would range from C to B. The pre-1940 share is a Census survey estimate (±6.1 points). The founding year is the first post office, not a stated founding date.
Founding year: the first post office (other dates in Quick answers). Homes: Census ACS 2020–24. National Register: National Park Service, May 2026 list; each listing counted once (boundary changes and added documentation belong to their listing), and a historic district counts its contributing buildings. How TownRatings grades history →
What stands out about Spring Bay Township’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
Lost two-thirds of its people between 1870 and 1930, then grew 5-fold.
16 censuses, 1870–2020.
U.S. Census Bureau decennial counts, from the census table on Spring Bay Township’s Wikipedia page.
On the map
Spring Bay Township on the map, 1893 to 1996
Every edition of the U.S. Geological Survey’s map of Spring Bay Township. Tap a year, or press play to watch the town change.
1893Dunlap sheet · 1:62,500
U.S. Geological Survey historical topographic maps (public domain), via Esri’s collection of the scans. The red ring marks the center of Spring Bay Township.
The story so far
Spring Bay Township, in brief
Wikipedia doesn’t have a history of Spring Bay Township yet. The photos, dates and memories neighbors add here are how it gets written.
Spring Bay is a village in Woodford County, Illinois, United States. As of the 2020 United States census, the village population was 474, up from 452 in 2010. The village is part of the Peoria, Illinois Metropolitan Statistical Area.
Its first post office opened in 1848. Between the 2010 and 2020 censuses its population fell from 2,643 to 2,536 (-4%).
Intro from Wikipedia. Population: U.S. Census Bureau.
From the old history books
What they wrote about Spring Bay Township in 1878
Passages that mention Spring Bay Township, cut from the printed page as they were published.
The Past and present of Woodford County, Illinois1878 · page 300Read the page →
Read the text
Spring Bay, and, in the Fall of 1838, returned to Cincinnati. C. A. Genoways came back to their claim in 1840, and, after improving it, brought out his mother in 1842. She remained with him until her death, in 1856. Mr. Genoways is the present Supervisor of Spring Bay Township, an office he has filled for several terms, and was Constable for twenty-four years in succession. He is now living in the village, and has been in mercantile business for several years, but still owns the original homestead.
Text read by machine from the scan; it may contain errors.
Scans and text from the Internet Archive. Books published in 1930 or earlier, which are in the public domain.
By decade
No old photos in the archives yet
Weddings on Main Street, storms, parades, school pictures, the old store. If it’s in your family album, it belongs here.
Be the first to add onePhotograph a print flat, in daylight, no flash.
The Spring Bay Township post office opened in 1848, the earliest record of the town by name (U.S. post office records).
How does Spring Bay Township rank for history?
Spring Bay Township is more historic than 50% of U.S. towns, #404 of 768 in Illinois. The History grade combines the town’s founding era, the share of homes built before 1940 and its National Register listings. It’s a character grade, so it isn’t part of the overall grade. How it works.
How old are the homes in Spring Bay Township?
10% of Spring Bay Township’s homes were built before 1940 (Census estimate, ±6.1 points), against a typical 11% for an Illinois town; the median home was built in 1970.
Founding dates: Wikidata, Wikipedia, the U.S. post office records of Blevins & Helbock (CC0) and the Census. Homes by year built: Census ACS 2020–24. National Register of Historic Places: National Park Service (list of May 22, 2026). Old photos, postcards and papers: Wikimedia Commons, the Library of Congress and other public archives, credited on each item’s page. Maps: U.S. Geological Survey historical topographic maps (via Esri) and Sanborn fire-insurance maps (Library of Congress). History text and census tables: Wikipedia (CC BY-SA 4.0). Places that used to be: USGS Geographic Names Information System (2021).
From U.S. Geological Survey historical maps, U.S. Census counts (via Wikipedia), the USGS Geographic Names Information System and old county and town histories (Internet Archive). Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
