Barbara Cartland was one of the most prolific authors ever, with more than 700 novels to her name. According to Wikipedia, in total they sold in the ballpark o

Barbara Cartland was one of the most prolific authors ever, with more than 700 novels to her name. According to Wikipedia, in total they sold in the ballpark of a billion copies. Then again, I guess it could be argued she basically wrote the same book more than 700 times.