Joseph Curwen was a merchant and sorcerer who settled in Providence in the 1690s, secretly performing rites to raise and interrogate the dead using their "essential salts." His apparent agelessness aroused suspicion, and a vigilante party destroyed him in 1771.
His written knowledge survived and was unearthed by his descendant Charles Dexter Ward. Curwen was resurrected and successfully usurped Ward's body and existence.