Who was the inspiration for The Simpsons’ Troy McClure?

Who was the inspiration for The Simpsons’ Troy McClure?
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I’m not sure what exactly my kid brain thought, other than maybe every Simpsons character was a unique inspiration that Matt Groening himself just thought up on his own. I definitely missed the stereotypes and archetypes and most of the satire at first, but damn, give me a break, I was a kid!

Turns out many of the characters in The Simpsons were based not only on archetypes, but even real people. My parents surely caught that right away, as many of those references came more from their generation, or even their parents’ generation.

Which is all to say that Springfield’s default celebrity, Troy McClure (voiced by the incomparable Phil Hartman, RIP), was actually inspired by a real person. Who was it?