Diocese
From Official Wiki of the Renaissance Kingdoms
The term diocese refers to the religious territory governed by a bishop who presides over the cathedral.
A diocese may include one or more parishes under its authority.
The boundaries of dioceses do not necessarily follow the boundaries of duchies.
All dioceses belong to a province.
In every province there is a diocese known as the metropolitan diocese, which is where the archbishop of the province is based. This diocese remains, however, a diocese like any other.
A diocese that is not metropolitan is called a suffragan diocese.