Unknown. New York World-Telegram and the Sun Newspaper Photograph Collection (Library of Congress). · Public domain

Lenny Bruce made explicit political, religious, and sexual material part of stand-up comedy's vocabulary, and paid for it: his 1964 obscenity conviction, for material that reads as tame today, became a landmark free-speech case and effectively ended his career, though New York's governor pardoned him posthumously in 2003. Rolling Stone later ranked him third on its list of the best stand-up comedians of all time, behind only Richard Pryor and George Carlin.