The Vicariate Apostolic of Eastern Oceania was a Roman Catholic missionary jurisdiction for some of the South Sea (Pacific) islands from 1833 till 1848.
The whole of Oceania had at first been entrusted by the Roman Congregation Propaganda Fide to the Congregation of the Sacred Hearts of Jesus and Mary (1825); but the territory proving too large, the western portion was afterwards formed into an Apostolic vicariate and given to the Society of Mary (1836), Bishop Pompallier being appointed Apostolic Vicar of Western Oceania.
The boys' schools were conducted by local lay teachers; the colleges and the seminary by priests.
The islands were divided into districts, with resident missionaries who assembled every month for an ecclesiastical conference.
The vicariate has given to the Church the proto-martyr of Oceania, Saint Peter Chanel.