On its age, its old homes and the National Register, Manlius Township is more historic than 80% of U.S. towns, #176 of 768 in Illinois. All 2 inputs are above most U.S. towns; its share of homes from before 1940 ranks highest and its National Register listings lowest.
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HistoryA character grade: shown, never part of Manlius 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 Manlius Township’s 3.3 sits above most of its state (71% of Illinois towns have fewer) while its 2 historic buildings outnumber those of 60% of U.S. towns.
How sure. Graded on two of the three inputs, so a change in either one moves the letter more than it would with three. The pre-1940 share is a Census survey estimate (±4.4 points).
Founding year: our sources. 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 Manlius Township’s past
Read from the archive, the National Register and the record. The page puts what stands out first.
Every edition of the U.S. Geological Survey’s map of Manlius Township. Tap a year, or press play to watch the town change.
1892Marseilles 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 Manlius Township.
The story so far
Manlius Township, in brief
Wikipedia doesn’t have a history of Manlius Township yet. The photos, dates and memories neighbors add here are how it gets written.
Manlius Township is located in east-central LaSalle County, Illinois. As of the 2020 census, its population was 6,150 and it contained 2,730 housing units. It contains the town of Seneca and the eastern part of Marseilles.
Its population held steady between the last two censuses: 6,275 in 2010, 6,150 in 2020.
Intro from Wikipedia. Population: U.S. Census Bureau.
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.
Manlius Township is more historic than 80% of U.S. towns, #176 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 Manlius Township?
21% of Manlius Township’s homes were built before 1940 (Census estimate, ±4.4 points), against a typical 11% for an Illinois town; the median home was built in 1977.
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 and the USGS Geographic Names Information System. Archive images are copied here with their credits and licenses, shown on each photo’s page. Refreshed monthly.
