The ecclesiastical province of Barcelona includes the Metropolitan's own archbishopric and the following suffragan sees : As per 2014, it pastorally served 2,116,479 Catholics (79.7% of 2,657,000 total) on 340 km² in 214 parishes and 153 missions with 826 priests (396 diocesan, 430 religious), 46 deacons, 3,092 lay religious (639 brothers, 2,453 sisters) and 19 seminarians.

While local tradition and catalogues date back the first bishop, San Eteri, considered a disciple of Saint James the Great, to the very first Apostles, historical evidence seems to be undisputed from the third century onwards, when bishop Pretextat attended the Council of Sardica in 343.

During the Visigothic Kingdom, Barcelona became one of the fourteen dioceses of the ecclesiastic province of Tarragona.

Disregarding another year-lasting de facto sede vacante from 1808 to 1814 during the Napoleonic Wars, Barcelona and its diocese kept on growing richer and more powerful.

[1] The Catholic Encyclopedia states that “The See of Barcelona, unlike most very ancient sees, whose origins are obscure, has preserved catalogues of its bishops from Apostolic times, and although all the names given cannot be admitted as authentic, the greater number are handed down in all the catalogues.”[2] The list includes:[3] In the twelfth century the diocese was restored by Ramon Berenguer, Count of Barcelona.