Q. 1. What is a Diocese?
A. 1. In the Roman Catholic Church, the pope is the Bishop of the Diocese of Rome. Over and above that, he creates the other Catholic dioceses throughout the world and appoints their Bishops. The word "diocese," originating from the Greek language, means "administration." Such is the district under the supervision of a bishop.
In simple terms, a Diocese is a territory that contains a number of parishes. It has one Bishop who oversees that territory (Diocese) and its parishes.
A diocese also may be referred to as a bishopric or episcopal see, though strictly the term episcopal see refers to the domain of ecclesiastical authority officially held by the bishop, and the term bishopric to the post of being bishop.
As of January 2015, in the Catholic Church there were 2,851 regular dioceses: 1 papal see, 641 archdioceses (including 9 patriarchates, 4 major archdioceses, 551 metropolitan archdioceses, 77 single archdioceses) and 2,209 dioceses in the world.