Dr. Hahn studies and teaches southern history, agriculture, business and economic history, and especially the history of technology. Her first book explored the interactions between the tobacco industry and tobacco agriculture over several centuries and examined the emergence of the many tobacco varieties in response to market demand and regulatory context.  Her second book (with Bruce E. Baker) concerned cotton futures trading in the early twentieth century, and she has now published an undergraduate-level history-of-technology treatment of the Industrial Revolution (and antebellum cotton production).