No, the composer Johny Mercer did NOT live in, nor own this home. However, his grandfather did build it, and hence it's name. The house was made famous after the book "Midnight in the Garden of Good and Evil" was written by John Berendt. The story tells of a wealthy Savannah antiques dealer; Jim Williams, who owned the home during the 1980's, and shot and killed his "lover" Danny Hansford after an arguement erupted between the two. Williams has since died as well, and at this writting the house is currently for sale. The asking price is a cool 8.92 million dollars.
This building dates to 1886 and was a center of commerce when Savannah was the world's foremost cotton port. The world's cotton prices were set right here, in this building.