Fr. Isaac Hecker (1819–1888)

One of the most famous Catholic converts of the nineteenth century (along with his friend, Orestes Brownson), Hecker founded the Paulist fathers in 1858.

Links

Catholic Encyclopedia * Paulists

Book

D. O'Brien, Isaac Hecker: An American Catholic 

Diary Isaac T. Hecker, the Diary: Romantic Religion in Ante-Bellum America