Jure divino

The divine right of kings, divine right, or God's mandate is a political and religious doctrine of royal and political legitimacy. It asserts that a monarch is subject to no earthly authority, deriving the right to rule directly from the will of God. The king is thus not subject to the will of his people, the , or any other estate of the realm. It implies that only God can judge an unjust king and that any attempt to depose, dethrone or restrict his powers runs contrary to the will of God and may constitute a sacrilegious act. It is often expressed in the phrase "by the Grace of God", attached to the titles of a reigning monarch.

In the pagan world, kings were often seen as either ruling with the backing of heavenly powers or perhaps even being divine beings themselves. However, the Christian notion of a divine right of kings is traced to a story found in 1 Samuel, where the prophet Samuel anoints Saul and then David as mashiach or king over Israel. The anointing is to such an effect that the monarch became inviolable, so that even when Saul sought to kill David, David would not raise his hand against him because "he was the Lord's anointed".

Adomnan of Iona is one of the earliest Christian proponents of this concept of kings ruling with divine right. He wrote of the Irish King Diarmait mac Cerbaill's assassination and claimed that divine punishment fell on his assassin for the act of violating the monarch. Adomnan also recorded a story about St Columba supposedly being visited by an angel carrying a glass book and telling him that he needed to ordain Aedan mac Gabrain as King of Dal Riata, but Columba initially refused and to this response, the angel answered by whipping him and demanding that he perform the ordination because God had commanded it. The same angel then visited Columba on three successive nights, and then finally Columba agreed and Aedan came to receive ordination. At the ordination Columba told Aedan that so long as he obeyed God's laws, then none of his enemies would prevail against him, but the moment he broke them, this protection would end and the same whip with which he had been struck would be turned against the king. Adomnan's writings most likely influenced other Irish writers, who in turn influenced continental ideas as well. Pepin the Short's coronation may have also come from the same influence. The Carolingian dynasty and the Holy Roman Emperors also influenced all subsequent western ideas of kingship.

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