Giru Marcelli, located in present Algeria, was among the many town in the Roman province of Numidia which were important enough to become a suffragan diocese in the papal sway, but faded completely during the 6th century advent of Islam.
Its only historically documented bishops were:
Victor, partaking in a council held in 256 at Carthage by its bishop Saint Cyprianus on the 'lapsed Christians' who accepted forced pagan sacrificing to avoid martyrdom.
Pascentius, who participated in the synod called at Carthage by Hunerik of the Vandal Kingdom in 484, whereafter he was exiled, like most Catholic incumbents, unlike their Donatist heretic counterparts.
Titular see
The diocese was nominally restored in 1933 as Titular bishopric of Octava (Latin) / Ottava (Curiate Italian) / Octaven(sis) (Latin) (Latin adjective).
It has had the following incumbents, of the fitting Episcopal (lowest) rank, with archiepiscopal exceptions:
Titular Archbishop: Emile Maurice Guerry (1966.02.15 – death 1969.03.11) as emeritate; previously Titular Archbishop of Acrida (1940.05.31 – 1952.12.02) as Coadjutor Archbishop of Cambrai (France) (1940.05.31 – 1952.12.02), succeeding as Metropolitan Archbishop of Cambrai (1952.12.02 – 1966.02.15)
