In 1844, it was established as Apostolic Vicariate of Melanesia (a pre-diocesan jurisdiction, entitled to a titular bishop and exempt, i.e. directly subject to the Holy See) on territory split off from the Apostolic Vicariate of Western Oceania.
It lost territories repeatedly, to establish : On 14 November 1922, it was renamed after its see as Apostolic Vicariate of Rabaul.
On 5 July 1957, it lost territory again to establish the Apostolic Vicariate of Kavieng (now its suffragan diocese).
Its ecclesiastical province comprises, besides the Metropolitan's Archdiocese, the following suffragan bishoprics : (all Roman Rite; so far missionary members of Latin congregations)
This article on a Roman Catholic diocese in Papua New Guinea is a stub.