Marcantonio Colonna is the pen name of Henry Sire (H. J. A. Sire), an author and historian. Sire was born in 1949 in Barcelona to a family of French ancestry. He was educated in England at the Jesuits’ centuries-old Stonyhurst College and at Exeter College, Oxford, where he gained an honors degree in Modern History. He is the author of six books on Catholic history and biography, including one on the famous English Jesuit, writer, and philosopher Father Martin D’Arcy, SJ. The Dictator Pope is the fruit of Henry Sire’s four-year residence in Rome from 2013 to 2017. During that time he became personally acquainted with many figures in the Vatican, including cardinals and Curial officials, together with journalists specializing in Vatican affairs.