The Bishop of Ostia is the head of the suburbicarian diocese of Ostia, one of the seven suburbicarian sees of Rome. The position is now attached to the post of Dean of the College of Cardinals, as it has been since 1150, with the actual governance of the diocese entrusted to the Vicar General of Rome.
Ostia and Velletri, "Ostia e Velletri" in Italian, was a single suburbicarian diocese from 1105 to 1914. In 1914, Velletri (now Velletri-Segni) was split off as a separate suburbicarian diocese. Starting then, a new Dean would add the see of Ostia to the suburbicarian see he already had.
Bishops of Ostia and Velletri, since 1900
Serafino Vannutelli, 1914-1915
Vincenzo II Vannutelli, 1915-1930
Gennaro Granito Pignatelli di Belmonte, 1933-1948
Francesco VIII Marchetti Selvaggiani, 1948-1951
Eugène Tisserant, 1951-1972
Amleto Giovanni Cicognani, 1972-1973
Luigi Traglia, 1974-1977
Carlo Confalonieri, 1977-1986
Agnelo Rossi, 1986-1993
Bernardin Gantin 1993-2002
Joseph Ratzinger 2002-2005
Angelo Sodano, since 2005
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Suburbicarian Diocese of Ostia Wikipedia (Text) CC BY-SA
