Duffy's business would become one of the major publishers of Irish nationalist books, bibles, magazines, Missals and religious texts throughout the 19th and 20th centuries.
In 1830 he founded his own company, James Duffy and Sons and issued Boney's Oraculum, or Napoleon's Book of Fate, which experienced huge sales.
[3] Another great editorial success was achieved when he collaborated with Charles Gavan Duffy (no relation) from 1843 to 1846 to publish poetry from the writers of The Nation.
A second series began in 1862, renamed Duffy's Hibernian Sixpence Magazine, with Meehan as editor, which extended to six volumes and ended in June 1865.
These and other relatively cheap magazines took advantage of the new-found confidence in home-grown literature and also offered an outlet for Irish authors.