Charles the Fat: Carolingian Unity and the Crisis of Power (884–888) · EARLY MIDDLE AGES
In 887, Charles the Fat’s authority collapses. In the Carolingian world, a king is not only an heir: he must be able to defend the realm, dispense justice, and hold together a coalition of great men.
In November 887, Charles convenes an assembly at Tribur, near Mainz. East Frankish nobles, led by Arnulf of Carinthia, deprive him of his titles. Arnulf enjoys a strong military reputation, and the rupture is justified in the name of effectiveness and protection.
Charles holds many titles, but his power is vulnerable:
The feeling that the king “does not act” or “acts badly” can break obedience.
The deposition is a key moment: it shows Carolingian unity is not guaranteed by dynasty alone. Great men can withdraw support, and sovereignty becomes more conditional.
This is not an instantaneous switch everywhere: in West Francia, succession shifts mainly after Charles’s death in 888, and some spaces (such as Lotharingia) do not follow Arnulf immediately.