This cemetery is located on 606 South Church Street, Decatur, Macon County, Illinois.
Apparently, this place is known as one of the most haunted sites in the U.S. Please see: Only in Your State, Haunted Illinois, Medium.com, and Springfield Ghost Society.
Everywhere is Haunted describes it as such:
It has a chair, called the Devil's Chair, where people purportedly make deals with the devil. The legend of the Devil’s Chair, or haunted chair, as it is some times known, has been handed down through folklore. The chair is actually a mourning chair. It was placed by a grave, so that family and friends would have a place to sit when they visited the deceased. Mourning chairs are considered to be funerary sculpture. According to various superstitions, when someone sits on the chair, they will incur bad luck, or die within a year. Other legends promise good luck, or riches.
Greenwood’s Devil’s Chair Seat of the Chair According to the legend of the Devil’s Chair in Greenwood Cemetery, if you sit on the chair at a certain time, you can make a pact with the Devil. You will get anything you want for seven years. At the end of the seven years, the devil comes to claim your soul. Many cemeteries have removed their mourning chairs because of vandalism. Greenwood’s chair remains…