"the Marquis de Sade"
The only known authentic portrait of de Sade
Public DomainThe only known authentic portrait of de Sade

The Marquis de Sade (1740-1814) was a French nobleman whose name is the origin of "sadism".  He was a scandalous figure who spent much of his life in prison or mental asylums as a result of the obscenity and blasphemy of his work.  He was the author of several books which combine philosophy with pornography, frequently of a violent or peverse nature, and express his libertine political, social and sexual views.