The other groups of ecclesiastical buildings in Adelaide still serve their congregations. However, within the vicinity of St Paul’s, the well-to-do began to move out to the suburbs, selling off their fine residences to developers from about the first decade of the 20th century. The electric tram, ease of transport and increased mobility helped this trend. Movement from North Terrace, in particular, was only one part of the overall demographic change within the city, which saw a slow decline in population from 1914 when it peaked at almost 43,000.
The most prominent North Terrace resident and member of St Paul’s, Henry Ayers, died in 1897 and the family home (Ayers House) was vacated by the family in 1901, although the surviving members remained associated with St Paul's for many years to come. Henry Ayers’ daughter, Lucy, donated the Tiffany windows that were installed in the church in 1909. These and a number of other important stained glass windows were removed when the church was deconsecrated in 1983.
St Paul’s had been long associated with many leading political men, captains of industry and their families. Even families who lived in the country, such as the Bagots of Beefacres and the Bowmans of Enfield, had their children baptised at this church. Children of the Ayers family and three Bonython children were also baptised here between 1905 and 1908.
The pew rents book shows that between 1890 and 1904 more than one hundred pews were rented on a regular basis. The list reads like a who’s who of Adelaide, and includes such names as Ayers, Schomburgk, Everard, Bray, Chapman, Gillman and Hamilton. However most of the congregation was made up of citizens of varied backgrounds from all parts of the city.
St Paul’s Church attracted so many establishment families not only because it was within walking distance from home, but also because it was a High Anglican church. In the 1860s St Paul’s and St Andrew’s of Walkerville were the first churches in South Australia to use “innovations in ceremonial and church ornaments” and the first to gradually introduce further restoration of pre-Reformation church practice. The Very Reverend Dean Russell was responsible for introducing “Anglo-Catholic” doctrines into St Paul’s when he became the incumbent in 1860. He lived in the rectory from 1863 until his death in 1886. The Reverend John Owen succeeded him in 1887.
Russell was born in 1825 and educated at both Edinburgh and Dublin universities. His early ecclesiastical life was in the south of England before he took up his first position in South Australia as incumbent of St John’s, Adelaide, in 1855. He was incumbent of St Paul’s in 1860, canon of Adelaide in 1867, dean of Adelaide in 1869 and vicar-general in 1878. He took an active part in all social movements, especially those relating to the working classes and the promotion of temperance.
It is well built and of unusual design. Bluestone rubble is tuck pointed and arches are of well-gauged brickwork. The porch is of particular interest and suggests a pattern-book design, as does the whole composition, with its Dutch gables but rather clumsy massing. No architect for this building has been found, but Morgan and Gilbert in Early Adelaide Architecture 1836 to 1886 (1969) state that it was built “probably to the design of a man without training as an architect who remembered rectories in England”.