[1] Fr James Dixon, a convict priest, ministered in Sydney from 1803 to 1809 with the title Prefect Apostolic of New Holland.

Until 1834, the territory of the entire Australian mainland (including what is now the Archdiocese of Sydney) and the island of Tasmania was a distant outpost of the Vicariate Apostolic of Mauritius.

At that time, the Archdiocese of Sydney included the whole of the eastern portion of the continent, comprising what are now known as the states of New South Wales, Victoria and Queensland.

At present, the Archbishop of Sydney is metropolitan of all the dioceses of New South Wales, with the exception of portions of the Archdiocese of Canberra and Goulburn, which are geographically situated outside the Australian Capital Territory.

Constructed in the Geometric Decorated Gothic Revival style based on the designs of William Wardell, a foundation stone for the current cathedral was laid in 1868, with a dedication Mass held in 1882.

St Mary's Cathedral Choir, the oldest musical institution in Australia, is formed of approximately 40 choristers and sings at High Mass every Sunday and on special holy days.

It serves men who are in formation for diocesan priesthood for the Archdiocese of Sydney and a number of dioceses from the province of New South Wales and beyond.

Standing for 'Christ in the Third Millennium', Xt3 is a content-driven social networking site launched at World Youth Day 2008, held in Sydney.

[8] On 19 July 2008, before a congregation of 3,400 assembled in St Mary's Cathedral, Pope Benedict XVI lamented that child sex abuse had taken place and the pain it caused.

His statement reads:[9] "Here I would like to pause to acknowledge the shame which we have all felt as a result of the sexual abuse of minors by some clergy and religious in this country.

On 21 July 2008, before flying out of Australia, Pope Benedict met at St Mary's Cathedral, Sydney, with two male and two female victims of sex abuse by priests.

[10] The Premier of New South Wales, Morris Iemma, said that "Hopefully it will be a sign of righting the wrongs of the past and of a better future and better treatment by the church of the victims and their families.