(Latin: sedes, seat)
A territory over which a bishop rules or did rule.
See and diocese are synonymous words.
The creation of new sees, and the various modifications (as division, suppression, and change of boundaries) to which they are subject, is reserved to the Holy See.
Episcopal sees began with the successors of the Apostles.
In early Christian times the large cities were all episcopal sees, and later, when rural districts were able to support a bishop and his officials, sees were erected in smaller towns.
See the appropriate page for a list of dioceses profiled in this document.
New Catholic Dictionary