The Vatican's opening of its archives in 2006 for the period of the papacy of Pius XI (1922-1939) has prompted a burst of historical research which is not only shedding new light on the role of the Holy See and the Church in this period of extraordinary political and social turmoil, but also on some of the major world events of this period. In 2008, a number of institutions created a research network, bringing together scholars from different countries who are working in these archives and highlighting its emerging work to the broader scholarly community. This book represents the proceedings from a conference of this research network, held in Providence, Rhode Island, at the Brown University in October 2010. (Series: Christianity and History. Series of the John XXIII Foundation for Religious Studies in Bologna - Vol. 11)