He received his early education at Drogheda grammar school (where his mother hailed from) and at Downpatrick, after which he entered St Patrick's College, Maynooth in 1826.
In 1842 he was chosen by Pope Gregory XVI to be the first Vicar Apostolic of Ceylon (now Sri Lanka), but he refused the dignity as also the Bishopric of Down and the Archbishopric of Armagh.
Having published his translation of Gottfried Wilhelm von Leibniz's System of Theology in 1850, he was occupied on his Life of Cardinal Mezzofanti which appeared in 1858.
In a memoir written later, Wiseman wrote "the professors and the students, over five hundred in number, in full academic costume, were in waiting with the college grounds, and accorded to their illustrious visitor a thoroughly Irish welcome".
[6] Cardinals Nicholas Wiseman - the first Archbishop of Westminster - and John Henry Newman alike counted him as an intimate friend, and the latter wrote of him: "He had perhaps more to do with my conversion than any one else".