While she started work on Frankenstein at Byron's villa in Geneva, the ghost story bit is largely apocryphal (the power of modern cinema!). More importantly, she was reading Ovid at the time which introduced her to the idea of Prometheus which was to be one of the central philosophical pivots of the work. Moreover, she is more commonly known as
Mary Wollstonecraft Shelley, in much the same way as F Scott Fitzgerald is not known as F Fitzgerald... I am relinking accordingly.
sjc