[1][2] In the second half of the 19th century, the land where the church building now stands belonged to Mr. Michael Dawson of Brunswick.

[3] The church was named in honour of Saint Ambrose (340–397), who served as the Archbishop of Milan in Italy in the fourth century AD, after an Italian family from Milan who lived in Brunswick suggested it.

[3] Nine years later, in 1899, the church building was extended, with additional transepts, a sanctuary, two chapels, a porch and a baptistry.

[3] The church building was designed in the Gothic Revival architectural style, with a cruciform plan.

[2][3] There is also an organ dating back to the nineteenth century, and stained glass windows.