How did the Belasco House come to be known as "Hell House"?

Hell House earned its nickname through the infamous event that occurred there during Emeric Belasco's residence there before and after his death. The Hell House moniker described the atmosphere created by ungodly rituals, horrible acts of blasphemy and perversion that occurred under the silent influence and supervision of Emeric Belasco. It is considered the most haunted house in the world.