Tryntje Helfferich received her M.A. from the University of New Mexico, Albuquerque, and her Ph.D. in early modern European history from the University of California, Santa Barbara. She studies central Europe and France during the early modern period (1450-1815), with a particular focus on the Reformation era (1500-1650) and the period of the Thirty Years War (1618-1648). She is interested in the history of war and society, the history of religion, early modern European gender history, and diplomatic history. Her publications include The Essential Thirty Years War (Hackett, 2015); On the Freedom of a Christian (Hackett, 2013); The Iron Princess: Amalia Elisabeth and the Thirty Years War (Harvard, 2013); and The Thirty Years War: A Documentary History (Hackett, 2009).