Joseph Curwen is the main antagonist of the short story The Case of Charles Dexter Ward by H.P. Lovecraft. He is a sorcerer and former shipping magnate who kills his descendent, Charles Dexter Ward.
Joseph Curwen was a successful merchant, shipping magnate, slave trader, and highly accomplished sorcerer, born in present-day Danvers, Massachusetts, seven miles from Salem, on February 18, 1662. Unknown to anybody but him and a few other sorcerers, Curwen could raise the dead and talk them from either the complete corpse or its "essential saltes" (derived from the ashes of said corpse). He used this ability to revive long-dead wise men and torture them to learn their secrets. He also had enough magic to summon the eldritch entity Yog-Sothoth to help him.
Curwen found a way to create a spell that would transcend time and inspire a descendant to become interested in him and his work and attempt to bring him back should he ever be slain. This proved to have been a good move, as he was forced to flee to Providence during the Salem witch trials, and the residents of Providence found out about his crimes and slaughtered him. Years later, a descendant of Curwen's named Charles Dexter Ward recovered his ashes and resurrected him. Although he first posed as a man named Dr. Allen, Curwen soon realised that he looked enough like Charles to pass for him, and therefore killed and posed as Charles before resuming his evil activities. However, his anachronistic mindset and behaviour lead authorities to certify him insane and imprison him in an asylum.
While Curwen is in the asylum, Ward's doctor Marinus Bicknell Willett investigates and discovers his headquarters; a bungalow built on the site of Curwen's farm. Here, Willett finds out the truth about Curwen and the means to reverse the resurrection spell. He also accidentally summons an ancient entity who is an enemy of Curwen and his associates. Passing out, the doctor wakes up and finds a note telling him to kill Curwen. Confronting him at the asylum, Willett reduces Curwen to ash by reversing the spell. News reports reveal that Curwen's prime co-conspirators and their households have met brutal deaths, and their lairs have been destroyed.