The tract Defensor pacis (The Defender of Peace) laid the foundations of modern doctrines of sovereignty. It was written by Marsilius of Padua (Italian: Marsiglio da Padova), an Italian medieval scholar. It appeared in 1324 and provoked a storm of controversy that lasted through the century. The context of the work lies in the political struggle between Louis IV, Holy Roman Emperor and Pope John XXII. The treatise is vehemently anticlerical. Marsilius' work was censured by Pope Benedict XII and Pope Clement VI.