Why did monarchs often claim the divine right of kings?

Explanation:  The divine mandate of kings was based on the will of God that was carried through kings. This is, therefore, an absolutist rule, one man rules unquestionably because it is by the will of God, and besides, one is a king by the blessing of the Church which can be seen not only as an affirmation of God's will, but also as a strong political influence over people. So that the reign of the king was unquestionable as a rule not subject to any earthly authority, though earthly political ties also aided the reign of the king, but primarily divine mandate was inviolable and people did not discuss it.

This, however, could continue until the phenomenon of the divine mandate was so filled with various corruption and things not peculiar to such a mandate that people began to realize that they could live without a king or without a divine mandate. This led to many revolutions and enlightenment movements throughout history.