During a barn raising in 1836, it was proposed that a town be incorporated on land belonging to Henry Randleman. The name "Centerville" was proposed, as the site was equidistant from Belleville, Columbia, and Pittsburg Lake. The town was platted on March 13, 1837. In 1880, its name was changed to Millstadt, as the name Centreville was in use by another nearby town.
Another account (Millstadt School website): "The story of how Millstadt developed out of 'Centerville' goes something like this. The current Centreville and our Centerville each had a post offices through which a great deal of mail became confused and mis-delivered. Our town's forefathers, upon applying for formal organization through the state, supposedly decided on the name 'Mittlestadt' or 'Middlestadt,' which means literally 'center city'; somehow the state misread the writing and sent back the papers reading 'Millstadt.' As you can guess, the governing group decided to keep that name as we had several mills at that time and the name fit."
In 1874, a German immigrant farm family was killed in a farming hamlet known as Saxtown, just south of the town. It made national headlines and became the subject of the book The Ax Murders of Saxtown. 
Schools, churches, cemeteries
- Elementary schools:
- High schools: (all are in nearby Belleville, Illinois)
- Churches in Millstadt:
Millstadt Water Tower, no longer used
Location of Millstadt in St. Clair County, Illinois.
Location of Illinois in the United States
|• Mayor||Michael H. Todd|
|• Total||3.35 sq mi (8.68 km2)|
|• Land||3.19 sq mi (8.25 km2)|
|• Water||0.17 sq mi (0.43 km2)|
| • Estimate
|• Density||1,217.20/sq mi (469.95/km2)|
|Time zone||UTC-6 (CST)|
|• Summer (DST)||UTC-5 (CDT)|
|Wikimedia Commons||Millstadt, Illinois|