The first building to house a Catholic Church in Greenhill stood on what is now the site of St Joseph’s Junior Cathedral School in 1857. Under the guidance of Fr Peter Lewis, this building acted as a church on Sunday and as a classroom within the week. The first Ursulines of Jesus Sisters arrived to teach the children of Greenhill in September 1860.

In 1865 the foundation stone was laid for a new church, which opened in October 1866, on the site of the current Parish Hall. Numbers of Children attending the school increased and as such the area below the new church was used as a classroom.

On the retirement of Fr Peter Lewis in 1873, the already established Church of St David in the City Centre was placed under the charge of the English Benedictines while Fr Basil Hurworth led the new Church of St Joseph.

By 1875, Fr Wulstan Richards had arrived in Greenhill as the first resident priest in the Church of St. Joseph, marking the separation of St David’s and St Joseph’s into their own respective parishes.

Fr Wulstan Richards called upon the talents of Peter Paul Pugin, son of Augustus Pugin, to design a new church in 1886. The Church of St Joseph was opened, unfinished, on 25th November 1888 by Dr Hedley, Bishop of Newport. The Stations of the Cross that currently hang in the Cathedral were brought from Antwerp by Fr Willibrod Van Volckxson and Fr Bede Cox was successful in obtaining Lord Petre’s Pipe Organ.

Aesthetic enhancements to the as yet unfinished Church of St. Joseph continued in the coming years. Peter Paul Pugin returned in 1899 to design the screen that currently separates the entrance from the body of the Church below the Organ Gallery. In 1901 the benches, Paschal Candlestick and mosaic dado were added.

1907 saw the arrival of a new High Altar along with decoration of the chancel and the installing of the previous High Altar with a new Reredos to the Blessed Sacrament Chapel. An altar and the Oil Painting Reredos were also added to St Joseph’s Chapel.

In 1919 the Parish, under Fr. Bernard Harrington, had cleared the debt the church had been under due to its construction, allowing for the consecration to take place. In preparation for the consecration, the pipe organ was dismantled and rebuilt along with additions and the Baptistery was completed.

On 4th October 1919 the church was consecrated and the War Memorial that stands at the church’s entrance was unveiled. The War Memorial featured the names of 120 parish members, including one woman from World War I. In 2000 the names of those who died from the parish in World War II were added to the Memorial.

The Girls’ Infants School building was added in 1930 with its foundation stone laid by Dr Mostyn, Archbishop of Cardiff,

In 1932 the Canon Louis Mooney was appointed parish priest, the first secular priest and first appointment to come from outside the Benedictine Order to serve in the Parish of St Joseph.

On 17th February 1987 it was announced that a third Diocese in Wales was to be created. Bishop Daniel Mullins, Auxiliary Bishop in Cardiff, was to take possession of the new see and the Church of St Joseph, Swansea was to be his Cathedral.

Work on the Church of St Joseph began once again to prepare for its elevation to Cathedral. The Sanctuary was extended forward with the High Altar re-modelled and placed in a new position. The Cathedra was installed where the High Altar had previously stood along with the surrounding presbyterium.

Bishop Daniel Mullins was enthroned as Bishop of the newly inaugurated Diocese of Menevia at the Cathedral Church of St Joseph on 19th March, 1987.

Today, the Cathedral stands as the Mother Church to the Diocese of Menevia and an outstanding symbol of the Catholic Faith in Wales' second city.