The Scots Presbyterian Church was founded in Sydney in the 1820s and the congregation has had to be relocated on several occasions to different sites in the Sydney CBD prior to moving back into its current site at 44 Margaret St, known as the Assembly Building in February 2006.

The building has been creatively redeveloped to include residential useage and at the same time the interior of the Church was redeveloped.

The new building retains its historical features and significance while providing the congregation with a modern house of worship.

John Dunmore Lang (1799 - 1878), was born near Greenock, Renfrewshire, Scotland, the eldest son of William Lang and Mary Dunmore. His father was a small landowner and strict Presbyterian. He was destined for the Church of Scotland ministry from an early age, and was educated at the University of Glasgow, where he excelled, graduating as a Master of Arts in 1820. In 1823 he was sent to be the first Presbyterian minister in the colony of New South Wales.

Arriving in Sydney, he found the Presbyterian Scots to be a small minority, dominated by an Anglican administration and outnumbered by the Irish Catholics, whom Lang, a fierce sectarian, hated and feared. There was no Presbyterian church in the colony and Lang demanded that the Governor, Sir Thomas Brisbane, provide public funds for one. When Brisbane refused, Lang returned to Britain, where he successfully lobbied the Secretary for the Colonies, Lord Bathurst, to reverse Brisbane's decision. The government was to supply one-third of the cost of the building and pay Lang £300.0.0 a year.

In 1826 he became the first Minister of the Scots Church. He demanded also that the Presbyterian Church be recognised alongside the Church of England as an established church in the colony, since New South Wales was, he said, a Scottish colony as well as an English one.

Lang remained as Minister of Scots Church for 52 years, although he was deposed by his own Church Synod in 1842 and for 20 years presided at Scots Church as an independent Presbyterian.

Dunmore Lang College, at Macquarie University in Sydney honours his name and a statue of him is in Wynyard Park.