Slight hijack: When Gerald Ford was President, two previously (in)famous people tried to assasscinate him. First Lynette “Squeakly” Fromme, one of Charles Mansons followers, and later Sarah Jane Moore, who organized the food giveaway demanded by the kidnappers of Patricia Herst.
On a related note, Squeaky’s failed assassination is one of the funnier foiled assassination plots I’ve read about. She had a magazine in the gun, but neglected to chamber a round first. So she’s all like draw clickclick TACKLED
The other assassination attempt (something like a week or two after the previous one) is noteworthy in that the guy who saved the President’s life had his own life pretty much ruined by it (he was a homosexual, and the unwanted publicity effectively outed him, causing him to be disowned by his family).
But now that someone has mentioned a duel, I’m not sure if Andrew Jackson was a celebrity at the time, but he was a known public figure when he killed Charles Dickenson in a duel. ISTR reading somewhere (though I can’t seem to find it right now) that the duel ruined his reputation for a time, thuogh he rebuilt it after the Battle of New Orleans.
How about Christian Brando (Marlon’s son)?
Was he actually famous before the trial? Sure his dad was but would anyone recognize him on the street?
Prison Break’s Lance Garrison can be added to the list.