The solemn beatification of Pope Pius IX in September 2000 celebrated the heroic virtue of one of the most influential figures of the nineteenth century. Born in 1792, Giovanni Maria Mastai Ferretti was elected Pope on June 16th 1846. His pontificate, the subject of this biographical study, lasted thirty-two years, the longest after that of St Peter himself. Elevated to the Papacy amid the historical backdrop of turmoil and revolution in Italy and Europe, he was also to play a central role in the drama of the Risorgimento that led to the creation of a united Italy. Publication of the English translation of Roberto de Mattei's acclaimed study of Pius IX marks the 150th anniversary of the Pope's solemn definition of the Dogma of Our Lady's Immaculate Conception. Roberto de Mattei holds the chair of Modern History at the University of Cassino (Rome), is vice president of the Italian C.N.R. (National Council for Research) and is well-known in Italy as a journalist and writer.