From a modern perspective, Austen and Shelley are the most important female authors of the period. Why is this; what could they possibly have in common?

Along with Pride and Prejudice, Frankenstein remains the most widely read novel of the period. How do you account both for its popularity and its importance? From a modern perspective, Austen and Shelley are the most important female authors of the period. Why is this; what could they possibly have in common? Please write in MLA format (7pages, excluding work cited) and firm thesis is necessary.