The northernmost part of the diocese covered what is today the Limpopo Province.
In 1957 Bishop Robert Selby Taylor decided to make Pietersburg the centre of the Archdeaconry of the North.
The diocese assumed arms around the time of its inception : Per fess Gules and Azure, a fess Argent between in chief a lion passant Or supporting a staff proper flying therefrom the banner of St George, and in base an anchor erect Or.
By 1889, the diocese had added a green border to the arms, possibly to reflect the colours of the South African Republic's national flag.
It removed the border after the republic had become a British colony again in 1902, and changed the upper half of the shield to blue.