Springfield Ohio up north in the States. .. where the Simpsons are.
Actually, nobody knows where the Simpsons are from.
The writers wanted them to be an average ‘simpleton’ (cunningly abbreviated to ‘Simpson’) family from a non-specific state.
They chose Springfield as there are so many Springfields in the US. In the episodes they also tease the audience never quite revealing which state they are from.
Here are the possibilities:
Springfield city, Florida
Springfield city, Georgia
Springfield city, Illinois
Springfield city, Kentucky
Springfield city, Massachusetts
Springfield city, Michigan
Springfield city, Minnesota
Springfield city, Missouri
Springfield city, Nebraska
Springfield city, Ohio
Springfield city, Oregon
Springfield city, South Dakota
Springfield city, Tennessee
Springfield town, Colorado
Springfield town, Dane County, Wisconsin
Springfield town, Jackson County, Wisconsin
Springfield town, Louisiana
Springfield town, Marquette County, Wisconsin
Springfield town, Otsego County, New York
Springfield town, Penobscot County, Maine
Springfield town, South Carolina
Springfield town, St. Croix County, Wisconsin
Springfield town, Sullivan County, New Hampshire
Springfield town, Windsor County, Vermont
Springfield township, Bradford County, Pennsylvania
Springfield township, Bucks County, Pennsylvania
Springfield township, Burlington County, New Jersey
Springfield township, Cottonwood County, Minnesota
Springfield township, Delaware County, Pennsylvania
Springfield township, Erie County, Pennsylvania
Springfield township, Fayette County, Pennsylvania
Springfield township, Huntingdon County, Pennsylvania
Springfield township, Kalkaska County, Michigan
Springfield township, Mercer County, Pennsylvania
Springfield township, Montgomery County, Pennsylvania
Springfield township, Oakland County, Michigan
Springfield township, Union County, New Jersey
Springfield township, York County, Pennsylvania
Edit: I found this regarding The Simpsons:
Where is Springfield? The short answer is: on your television. Springfield does not exist. It doesn't have a real state, and the fact that it has no state is nothing more than a running gag. Springfield is more like "Anytown, USA". It's as if all of America was compressed into a single town, or a single state. Springfield is everywhere and nowhere.
Proof? No state's capital city is called "Capital City". No state has ever had their flag. No state's motto is "Not just another state". And that's just the tip of the iceberg. There is an enormous number of geographical contradictions between episodes which make it impossible for Springfield to actually exist in any real American state.
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