Nicholas of Cusa’s Idea of a “Just War”

Although Nicholas of Cusa (1401–1464) does not explicitly speak about “just war” in his writings, the third book of his most important political work, The Catholic Concordance (De Concordantia Catholica), contains several text passages on feuds that reveal his idea of a “just war.” As a doctor of canon law, Cusanus rejected all kinds of feuds which often led to private wars among nobles. He saw the rampant feuds as a major reason for the decline and destabilization of the Holy Roman Empire. His idea of a “just war” is influenced primarily by many canonistic and moral-theological writings, especially the ideas of Thomas Aquinas in his Summa Theologiae. For Nicholas of Cusa war and violence are only justified under certain circumstances: if they are authorized by the emperor as supreme ruler or by the imperial courts, when there is a just cause, such as defence against external and internal enemies, and when they are done with the right intention, such as the restoration of peace.