The animated show's real location has become a long-running gag over the years, especially as Springfield is one of the most common town names in the US.
However, creator Groening has revealed that Springfield was named after the town of the same name in Oregon, his home state.
"Springfield was named after Springfield, Oregon," he told The Smithsonian.
"The only reason is that when I was a kid, the TV show Father Knows Best took place in the town of Springfield, and I was thrilled because I imagined that it was the town next to Portland, my hometown.
"When I grew up, I realised it was just a fictitious name. I also figured out that Springfield was one of the most common names for a city in the US. In anticipation of the success of the show, I thought, 'This will be cool; everyone will think it's their Springfield'. And they do."
Groening added that he hadn't revealed the true Springfield location as he "didn't want to ruin it" for the fans.
"Whenever people say it's Springfield, Ohio, or Springfield, Massachusetts, or Springfield, wherever, I always go, 'Yup, that's right'," he admitted.
Despite the revelation, Springfield was previously said to be on the border of Ohio, Nevada, Maine and Kentucky in The Simpsons Movie, which played along with the joke that it isn't located anywhere.
The Simpsons was renewed for a further two seasons by Fox last year.
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