Donatien Alphonse François, Marquis de Sade

Donatien Alphonse François de Sade (2 June 1740 – 2 December 1814), better known as the Marquis de Sade, was a French aristocrat, revolutionary politician, philosopher and writer, famous for his libertine sexuality. His works include novels, short stories, plays, dialogues and political tracts. He was a proponent of extreme freedom, unrestrained by morality, religion or law.

Reference
 * Assassins Creed Unity: Everything we know so far