Gary Gilmore (1940-1977) was convicted of two murders in Utah and later became famous for insisting his death sentence by firing squad be carried out. He was the first person executed in the U.S. after new death penalty laws were upheld by the U.S. Supreme Court. His famous last words were: 'Let’s do it!' A book was written about his crimes~ "Executioner's Song"
The word comes from French charlatan, a seller of medicines who might advertise his presence with music and an outdoor stage show.