“Why not, my child, yourself become a missionary?” Pope Leo XIII to Saint Katharine Drexel The mass migrations of peoples who immigrated to the United States in the 19th and early 20th centuries dramatically changed American life and the Catholic Church in the United States. These millions of peoples, principally from Ireland, Germany, Italy and Poland, flocked to urban parishes where they preserved their native languages and cultures as they began the process of entering into the American melting pot and fulfilling the American Dream of a better life.