William Hogan was born in Ireland and became a priest before emigrating to America around 1810. Assigned to St. Mary's parish in Philadelphia, he proved himself a popular priest. But he soon ran afoul of Bishop Henry Conwell, who resented his popularity and disapproved of his vigorous social life. When Hogan resisted Conwell's attempts to rein him in, Conwell suspended him. The trustees of St. Mary's rushed to Hogan's defense and Conwell soon had a full-blown schism on his hands. He eventually excommunicated Hogan in 1821 and then, like many American bishops in the 1820s, wrested control of the parish from the lay trustees.
Following his excommunication, Hogan managed a circus, studied law, and married twice, before reemerging in the 1840s as a leading voice of anti-Catholicism. He went on the lecture circuit, wrote belligerent essays in popular journals, and published in 1854 a book entitled, Popery as It Was and as It Is. The general tone of the latter is conveyed in the following statement: "I am sorry to say, from my knowledge of Roman Catholic priests ... that there is not a more corrupt, licentious body of men in the world."