The new diocese extends from the eastern edge of the Metropolis of Johannesburg, Gauteng Province, South Africa, to the borders of the Kingdom of Eswatini.
Apart from the urban and industrial areas, forming what is known as the East Rand, in which most of the parishes are situated, much of the Diocese is rural farming land, falling within the Province of Mpumalanga.
On the Feast of the Epiphany, 6 January 1990, the Diocese of South Eastern Transvaal, now Highveld, came into being.
David Beetge was elected to lead the diocese; he died on 27 September 2008.
The diocese registered a coat of arms at the Bureau of Heraldry in 1990 : Argent, two flanches Gules, a cross crosslet fitchy Azure; the shield ensigned with a mitre proper.