Akaroa Station, without a resident priest after 1851, was with other parts of Canterbury visited at intervals from Wellington. In 1860 Viard sent Fathers Seon and Chataigner, both Marists, to found the “Port Cooper Mission”. From the headquarters, established in Christchurch, further stations were gradually set up. Father Chataigner founded schools, introducing into the South Island the first teaching order of nuns, Sisters of Our Lady of the Missions, who opened their first school in Christchurch in 1868. As a result of the request of the Bishops of the Plenary Synod, held in Sydney in 1885, Rome created the diocese of Christchurch by papal brief of 10 May 1887. An English Marist, John J. Grimes, was appointed first bishop and consecrated in London on 26 July 1887. A zealous worker, he developed further the works of the Church, and, with the aid of donations from all parts of the world, he built the Cathedral of the Blessed Sacrament at a cost of £80,000 and dedicated it in 1905.

On his death, in 1915, Bishop Grimes was succeeded by Matthew J. Brodie, a priest of Auckland diocese, who was consecrated in Christchurch by the first Apostolic Delegate to Australia and New Zealand, Archbishop Cerretti, later Nuncio to France and a Cardinal. Bishop Brodie died in 1943 and his successor was Patrick Frances Lyons, a priest of the archdiocese of Melbourne. In 1950 Bishop Lyons was appointed auxiliary to Cardinal Gilroy, of Sydney, and as his successor Rome appointed Edward Michael Joyce, a priest of the diocese of Christchurch.

The increasing work of the Church in New Zealand led the Bishops to decide in 1946 on the division of the studies in seminary training. Accordingly, in 1947, the National Minor Seminary as the centre for philosophical studies was opened in Christchurch and its care committed to the Society of Jesus.