He was the third and youngest son of William Manning, a prominent merchant and slave owner,[3] who served as a director and (1812–1813) as a governor of the Bank of England[4] and also sat in Parliament for 30 years, representing in the Tory interest Plympton Earle, Lymington, Evesham and Penryn consecutively.

At this date he had ambitions of a political career, but his father had sustained severe losses in business and, in these circumstances, having graduated with first-class honours in 1830, he obtained the year following, through the 1st Viscount Goderich, a post as a supernumerary clerk in the Colonial Office.

[4] Manning resigned from this position in 1832, his thoughts having turned towards a clerical career under Evangelical influences, including his friendship with Favell Lee Mortimer, which affected him deeply throughout life.

Manning married Caroline, John Sargent's daughter,[7] on 7 November 1833, in a ceremony performed by the bride's brother-in-law, the Revd Samuel Wilberforce, later Bishop of Oxford and Winchester.

[5] Upon his death more than half a century later, a locket containing Caroline's picture was found on a chain around Manning's neck, by then a celibate Catholic cleric of many decades.

[5] In 1838 he took a leading part in the church education movement, by which diocesan boards were established throughout the country; and he wrote an open letter to his bishop in criticism of the recent appointment of the ecclesiastical commission.

[5][8] Newman's secession in 1845 placed Manning in a position of greater responsibility, as one of the High Church leaders, along with Edward Bouverie Pusey, John Keble and Marriott; but it was with Gladstone and James Robert Hope-Scott that he was at this time most closely associated.

That a civil and secular court had the power to force the Church of England to accept someone with such an unorthodox opinion proved to him that, far from being a divinely created institution, the Anglican Communion was a man-made creation and, even worse in his views, still completely controlled by Her Majesty's Government.

Several scholars consider Manning to be a key contributor to the papal encyclical Rerum novarum issued by Pope Leo XIII,[15][16]: 309  which marks the beginning of modern Catholic social justice teaching.

In 1888, Manning was interviewed by social activist and journalist Virginia Crawford, a fellow English Catholic, for The Pall Mall Gazette,[18] and was instrumental in settling the London dock strike of 1889[4] at the behest of Margaret Harkness.

In 1871, at St. Mary Moorfield, he said he hoped English womanhood would "resist by a stern moral refusal, the immodesty which would thrust women from their private life of dignity and supremacy into the public conflicts of men.

[22] In comparison to his polemical writings, The Eternal Priesthood is "austere" and "glacial",[21] arguing for a rigorous conception of the moral duties of the office.