The Medieval Church as a Military Power - Medievalists.net
Briefly

By the late 11th century, the Roman Catholic Church transformed into a potent military power, capable of generating its own armed forces for religious purposes. This evolution was facilitated by the Church's authority within the spiritual landscape of Latin Christendom, which allowed it to define just causes for war and to mobilize secular nobles. The Church could punish those who resisted its authority and incentivize military service with promises of sin remission. As lay piety grew, so too did the Church's influence, solidifying its role in military affairs.
By the late 11th century, the Roman Catholic Church started evolving into a powerful military controller, able to generate armed forces for religious purposes.
The Church's monopoly power in the spiritual realm allowed it to claim moral authority, defining just causes for war and mobilizing secular authorities.
The Church developed means to punish secular authorities for failing to support its military interests, notably through excommunication and the interdict.
In the early millennium, lay piety intensified throughout Latin Christendom, providing a stronger basis for the Church to assert its military influence.
Read at Medievalists.net
[
|
]