The Italian Roman Catholic diocese of Acquapendente was an ecclesiastical territory in Lazio, seated at Acquapendente Cathedral. It existed from 1649, when it was created in the place of the suppressed diocese of Castro, to 1986, when with other dioceses it was merged into the diocese of Viterbo, Acquapendente, Bagnoregio, Montefiascone, Tuscania e San Martino al Monte Cimino.
In 1649, in consequence of a conspiracy, Cristoforo Girarda, a Barnabite of Novara and Bishop of Castro, was assassinated in the Second War of Castro. In punishment of this crime, Pope Innocent X ordered Castro to be destroyed, and raised Acquapendente to the dignity of an episcopal city (Bull, 13 September 1649), directly under the Holy See. Its bishops, however, retained the appellation "post Castrenses." The first incumbent of the new See was the Hieronymite Pompeo Mignucci of Offida, who had been Archbishop of Ragusa. He took possession on 10 January 1650.
Erected: 13 September 1649
Latin Name: Aquipendiensis
Immediately Subject to the Holy See
This article incorporates text from a publication now in the public domain: Herbermann, Charles, ed. (1913). "". Catholic Encyclopedia. New York: Robert Appleton.