Bishopric of Tortona

Diocese of Tortona Dioecesis Derthonensis
Tortona Cathedral and the palace of Bishop on the right
Location
Country	Italy
Ecclesiastical province	Genoa
Statistics
Area	2,350 km2 (910 sq mi)
Population - Total - Catholics	(as of 2014) 281,420 274,695 (97.6%)
Parishes	314
Information
Denomination	Catholic Church
Rite	Roman Rite
Established	4th Century
Cathedral	Cattedrale di S. Maria Assunta e. S. Lorenzo
Secular priests	106 (diocesan) 58 (Religious Orders)
Current leadership
Pope	Francis
Bishop	Vittorio Francesco Viola, O.F.M.
Emeritus Bishops	Martino Canessa
Website
www.diocesitortona.it

The Diocese of Tortona (Latin: Dioecesis Derthonensis) is a Roman Catholic ecclesiastical territory in northern Italy, spanning parts of three regions of Piedmont (Province of Alessandria), Lombardy (Province of Pavia) and Liguria (Province of Genoa). It is a suffragan of the Archdiocese of Genoa and forms part of the ecclesiastical region of Liguria. The diocese claims to be one of the oldest in Lombardy and the Piedmont.

According to legend, which is, however, a late one, the first Bishop of Tortona was Marcian of Tortona martyred under the Emperor Hadrian. Francesco Lanzoni has pointed out that the list of bishops that leads back to Marcian of Tortona is a compilation of the 16th century and that its contents are highly suspect. Additionally, the story of Bishop Marcian depends on a hagiographical source of the 10th century, which is full of anachronisms. Fedele Savio points out that the earliest document referring to Marcian was written between 729 and 820, and that it neither calls Marcian a bishop nor the Bishop of Tortona; and, as he points out, the letter of Bishop Eusebius of Vercelli, written to the people of Tortona from his exile in Scythopolis in 356, makes no mention of a bishop. The Bishop of Tortona, Vincenzo Capelli, nonetheless organized an event in October 1875 to celebrate the 18the centenary of Martianus' episcopal consecration.

In the first half of the fourth century, Tortona was a suffragan of the diocese of Milan.

The first bishop, according to Fedele Savio, was St. Innocentius, who in his opinion was the immediate predecessor of St. Exuperantius (381), the first of whom we have certain historical record, and who was highly praised in a sermon of Maximus of Turin (or of Ambrose of Milan). Few other names of bishops of the early period are known; but from the tenth century the list is more complete.