Rev. John Christian MacCullagh was born on June 6, 1832, in Palmerstown, County Dublin, Ireland.

He was an Anglican priest. Educated at Clontarf Crescent and Trinity College, Dublin, he entered the Islington Mission College. In 1863, he travelled to Sydney, Australia, and entered Moore Theological College. He was ordained deacon at St. James's Pro-Cathedral, Melbourne in 1864. In 1866, he was ordained priest and was inducted as incumbent of St. Paul's Anglican Cathedral, Sandhurst, where the parish and the entire community flourished during his forty-six years of service. In 1907, he became vicar-general of the new diocese of Bendigo and acted as archdeacon from 1909 to 1914. MacCullagh had contributed scientific and religious articles to the Argus and the Bendigo Church News. He also published Sunday school lesson material and notes for theological students. He won repute throughout the whole district for his liberality and concern for those who suffered.

In 1865, he married Elizabeth Ince (1843–1870). He died on September 24, 1917, in Melbourne, Australia, almost penniless; for years giving his income to those who needed it.