Defensor pacis

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.

Defensor pacis extends the tradition of Dante's De Monarchia separating the secular State from religious authority. It affirmed the sovereignty of the people and civil law and sought to greatly limit the power of the Papacy, which he viewed as the "cause of the trouble which prevails among men" and which he characterized as a "fictitious" power. He proposed the seizure of church property by civil authority and the elimination of tithes. In his view, the Papacy would retain only an honorary pre-eminence without any authority to interpret the scriptures or define dogma.

As its name implies, it describes the State as the defender of the public peace, which is the most indispensable benefit of human society. The author of the law expresses will of the people, not of the whole populace, but of the most important part (valentior) of the citizens; these people should themselves elect, or at least appoint, the head of the government, who, lest he should be tempted to put himself above the scope of the laws, should have at his disposal only a limited armed force. This chief is responsible to the people for his breaches of the law, and in serious cases they can sentence him to death. The real cause of the trouble which prevails among men is the Papacy, the development of which is the result of a series of usurpations.

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