Maybe Charles Darwin, he could have been a bastard and those things didn't make it into the history books but I think he might be a safe bet.
Are you ready for the fire? We are firemen. WE ARE FIREMEN! The heat doesn’t bother us. We live in the heat. We train in the heat. It tells us that we’re ready, we’re at home, we’re where we’re supposed to be. Flames don’t intimidate us. What do we do? We control the flame. We control them. We move the flames where we want to. And then we extinguish them.
Impersonation is treason.