Complex sentence: The crimes of the Bishop of Riez in Provence, caused John to order the bishops of Gaul to confine him in a monastery; until a new bishop should be appointed, he bade the clergy of Riez obey the Bishop of Arles.
Split into simpler sentences: The crimes of the Bishop of Riez, in Provence, caused John to order the bishops of Gaul to confine him in a monastery. Till a new bishop should be appointed he bade the clergy of Riez obey the Bishop of Arles.