Capodanno was born on Staten Island, New York, joined the Maryknoll Missionaries and was ordained a priest by Cardinal Spellman 1957. After serving in Taiwan and Hong Kong, he became a Marine chaplain and was killed in action September 4, 1967. Known affectionately by his fellow soldiers as the "Grunt Padre," his cause for canonization was introduced by the Military Archdiocese in 2006.