Kenrick’s sermons were well-known and controversial. On many occasions Protestants outnumbered Catholics at his Sunday evening discourses to hear him speak on such topics as the mysteries of religion, doctrines of the Church, and evidences of Christianity. He is credited with many religious conversions. In his early years in St. Louis, immigrants from Europe called him the father of immigrants because of his understanding of their backgrounds and his encouragement of accepting priests who spoke various languages. Once, in 1868, when he returned from a visit to Ireland and Rome, a procession three miles long welcomed him. According to Mayor Darby, his spontaneous and welcome reception had never been awarded to any private individual in an unofficial government position in the country.