A captive archbishop is a Catholic priest who is named as archbishop of an archdiocese, which no longer exists as such. In the past, an archbishop was said to be in partibus infidelium.
A priest is sometimes dedicated to bishop and appointed as a Archbishop when he is employed in the Roman Curie or in the Diplomatic Service of the Holy See. He is then titular archbishop of an archdiocese that does not exist (or not more) as an active diocese. The same goes for priests nominated for cardinals and for that reason baptized with the title of archbishop.
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