The diocese came into being in 1847 with the consecration of the first bishop, Robert Gray, and was the first diocese of what was to become the Church of the Province of Southern Africa and subsequently the Anglican Church of Southern Africa. The original territory of the diocese, which had previously fallen under the Diocese of Calcutta, included the whole of Southern Africa.
In 1853, the territory was reduced by the creation of the Diocese of Grahamstown in the eastern parts of the Cape Colony and the Diocese of Natal in the Colony of Natal. In 1859, the Diocese of St Helena was created for Saint Helena and Ascension Island. In 1863, the Diocese of Bloemfontein was created, taking over all the territory north of the Orange River and the Drakensberg mountains. In 1866, J. Harries Thomas was archdeacon of Cape Town and H. Badnall, archdeacon of George; and N. J. Merriman, archdeacon of Bloemfontein (by then separated) was still a canon of Cape Town cathedral.[5] The territory of the Cape Town diocese was further reduced in 1911 by the creation of the dioceses of George and Kimberley and Kuruman. Finally, in 2005 the diocese was divided into three, with the part to north of the city of Cape Town becoming the Diocese of Saldanha Bay and the part to the east of the city becoming the Diocese of False Bay.
The diocese has borne arms since its inception. The arms, designed by Bishop Gray, combined elements of those of the dioceses of Durham (where Gray had been Bishop) and Bristol (his first chaplaincy, when his father was Bishop of Bristol) and of Baroness Burdett-Coutts, who financed the establishment of the diocese.
In their original form, the arms were : Quarterly Azure and Sable: I and IV, a lion rampant Argent; II and IV, three open crowns palewise Or; on a cross throughout Or an anchor in fess point Sable and in honour point the shield of arms of Baroness Burdett-Coutts; the shield ensigned with a Bishop's mitre proper.
The arms were revised by the College of Arms and granted in 1952. The revision consisted of replacing the Burdett-Coutts shield with a stag's head erased Gules, between the attires a pheon Azure. These arms were registered at the Bureau of Heraldry in 1968.[8]