Increasing numbers of settlers had begun to put pressure on mission stations resulting in New Zealand being made an independent vicariate by Rome in 1842. The rest of the area was named Central Oceania.
Father Philip Viard SM arrived in Sydney in 1845. Bishop Viard was ordained as Pompallier's coadjutor the following year and shortly after returned to New Zealand with Pompallier.
In 1846 Pompallier left for Europe and following his report to Pope Pius IX it was decreed in 1848 that New Zealand would be divided into two dioceses - Auckland and Wellington, with Wellington comprising all areas outside of Auckland.
When Pompallier returned to New Zealand in 1850 he brought French and Irish missionaries and the first Sisters of Mercy with him to work in the Diocese of Auckland.
In 1850 Bishop Viard as Apostolic Administrator of Wellington arrived with a band of Marist Fathers and Brothers, lay women and men. Within a short time, St Mary’s convent, the first Catholic school for girls was opened, staffed by the young women who came with the bishop. In 1861 the first Sisters of Mercy arrived from Auckland to further the work of education.
Although Viard believed that his main pastoral outreach should be to the rapidly-growing settler community, he still recognised the need for involvement with Maori, which led him to establish a St Joseph's Providence for Maori students at Thorndon, which opened on 8 September 1852.
This Providence should not be confused with that established by another Marist priest, Father Euloge Reignier, in Napier which the Sisters of Our Lady of the Missions staffed. In 1926, the school was renamed as St Joseph’s Maori Girls’ College and after the 1931 Napier earthquake was relocated to its present site in Greenmeadows. The Mission Sisters had arrived in Napier, then part of the Wellington Diocese in February 1865, and were soon involved in teaching both Maori and settler children.
On 8 September 1850 the foundation stone of St Mary's Cathedral was laid. In 1898 the cathedral was destroyed by fire and was replaced on the same site with the Sacred Heart Basilica in 1901. On 8 September 1987 the Basilica was rededicated as the Metropolitan Cathedral Church of the Sacred Heart of Jesus and Saint Mary His Mother.
After another visit to Europe in 1859 Pompallier returned in 1860 with members of the Franciscan Order and Suzanne Aubert, who became foundress of New Zealand congregation, The Daughters of Our Lady of Compassion. In 1860 Pompallier was made Bishop of Auckland by a papal brief. At the same time Bishop Viard was made Bishop of Wellington and ceased to be Pompallier’s coadjutor.
During the sixties, land wars took place between the Maori and Europeans. Financial depressions brought problems for Pompallier who left for Europe in 1868 and resigned his see in 1869. Bishop Thomas William Croke was nominated as Pompallier’s successor and he arrived in Auckland in 1870. He made significant organisational changes in the four years he was Bishop of Auckland, after which he transferred to Ireland and died there in 1902. Auckland was without a bishop until 1879 when Archbishop Steins SJ, a former Archbishop of Bombay, was appointed.
Bishop Viard died on 2 June 1872. A Marist priest, Father Francis Redwood, was ordained as his episcopal successor in London in March 1874, and arrived in New Zealand in November of that year. By papal brief of 13 May 1887 the see of Wellington was erected as an archdiocese, and Bishop Redwood was elevated to the office of Archbishop and Metropolitan of New Zealand.
Further south, the discovery of gold in Otago and Westland made Otago the most populated and prosperous province of the country. In 1864 the Holy See responded to this growth by creating the Diocese of Dunedin. The first bishop was Patrick Moran, transferred from South Africa accompanied by a priest and a group of Dominican nuns.
In 1860 Bishop Viard sent two Marists priests to found the ‘Port Cooper Mission’ in Canterbury. Further stations and schools were introduced in Christchurch with the Sisters of Our Lady of the Missions opening their first school in Christchurch in 1868. The Diocese of Christchurch was created by papal brief in 1887. An English Marist, Father John Grimes, was consecrated in London in 1887 and became Christchurch’s first bishop. The Cathedral of the Blessed Sacrament was dedicated in 1905.
In 1889 the first Marist House of Studies was founded in Wellington. In 1890 this seminary was moved to Meeanee where the first ordinations to the priesthood took place in 1893. The seminary was moved to Greenmeadows, near Napier, in 1911, which provided priests for the Society of Mary in New Zealand and also sent missionaries to work in the Marist Vicariates of Oceania.
Holy Cross Seminary – a national seminary for the training of diocesan clergy – was established in 1900 by Bishop Verdon of Dunedin. It was located in Mosgiel for nearly 100 years. At the end of 1997 the Seminary moved to Auckland and a year later moved to the present site in Ponsonby. In 1943 St Columban's Seminary was opened in Lower Hutt to train young men from New Zealand for the foreign missions.
In 1980 the dioceses were increased with the formation of the Hamilton and Palmerston North dioceses. Wellington priests, Fathers Edward Gaines and Peter Cullinane were appointed as Bishops of Hamilton and Palmerston North respectively. In 1988 Bishop Max Takuira Matthew Mariu SM was appointed as Auxiliary Bishop of Hamilton.