Mahony is born to Martin Mahony and Mary Reynolds. He is educated at the Jesuit Clongowes Wood College, in County Kildare, and later in the Abbey of Saint-Acheul, a similar school in Amiens, France and then at Rue de Sèvres, Paris, and later in Rome. He begins teaching at the Jesuit school of Clongowes as master of rhetoric, but is soon after expelled. He then goes to London and becomes a leading contributor to Fraser’s Magazine, under the signature of “Father Prout” (the original Father Prout, whom Mahony knew in his youth, born in 1757, was parish priest of Watergrasshill, County Cork). At one point he is director of this magazine.
Mahony is witty and learned in many languages. One form which his humour takes is the professed discovery of the originals in Latin, Greek, or mediaeval French of popular modern poems and songs. Many of these jeux d’esprit are collected as Reliques of Father Prout. He pretends that these poems had been found in Fr. Prout’s trunk after his death. He wittily describes himself as “an Irish potato seasoned with Attic salt.” Later he acts as foreign correspondent to various newspapers, and during the last eight years of his life his articles form a main attraction of The Globe.
Mahony spends the last two years of his life in a monastery and dies on May 18, 1866 in Paris reconciled to the Church.
The Reliques of Father Prout originally appear in two volumes in 1836 with illustrations by Maclise. They are reissued in Henry George Bohn‘s Bohn’s Libraries in 1860. Another volume, Final Reliques, is edited by Douglas Jerrold and published in 1876. The Works of Father Prout, edited by Charles Kent, is published in 1881. Facts and Figures from Italy (1847) is made from his Rome letters to London’s The Daily News.