It is the seat of the Diocese of Camden,[2] and it was listed on the National Register of Historic Places in 2003 as the Church of the Immaculate Conception.

They started to minister to Catholics in southern New Jersey in the 1740s where Catholicism was officially banned from being practiced.

In 1796 the Augustinian priests from St. Augustine Church started ministering to Catholics in the region.

They were followed sometime later by priests from the St. Mary's Cathedral in Philadelphia who served Camden until the Diocese of Newark was established in 1853.

Camden became a mission of the Catholic parish in Gloucester, which had received its first resident pastor in 1851.

Mass was celebrated a couple times a months in Camden in private homes and in public halls.

In 1867 the German Catholics who immigrated to Camden formed their own parish from Immaculate Conception, Saints Peter and Paul.

As the number of Catholics continued to increase in South Jersey, Pope Pius XI established the Diocese of Camden on December 9, 1937.

[5] The number of Catholics continued to increase in the diocese and Immaculate Conception's rather modest size necessitated St. Joseph's Church being named a pro-cathedral in the 1950s.

On April 4, 2008, Bishop Joseph Galante announced that the Cathedral of the Immaculate Conception would merge with Holy Name and Our Lady of Mount Carmel & Fatima parishes in Camden.