Clement Vallandigham (1820-1871). He also served two terms in the US House of Representatives.
I did not know he was mayor of Columbus. That's what I love about this place. You learn something new every day.
Methinks you’re confused. CV did not win election to mayor of Columbus. He ran for governor of OH and lost. He was later a contender for the Democratic nomination for president.
He was never expelled to Canada. After his arrest and conviction for a speech opposing the war he was expelled to the CSA, from when he made his way to Canada, then sneaked back in and ran the aforementioned campaign for gov.
He died in a truly unique way. While demonstrating how the victim his client was accused of shooting might actually have shot himself, he demonstrated how it might have happened.
Shot himself in the belly and died. Don’t know if that rather graphic demonstration was enough to get his client acquitted.