On December 12, 1989, Pope John Paul II appointed Schwietz as the seventh bishop of the Diocese of Duluth. He was consecrated on February 2, 1990 by Archbishop John Roach, with Bishops Robert Brom and Michael Pfeifer serving as co-consecrators, at the Cathedral of Our Lady of the Rosary in Duluth, Michigan.Schwietz served as episcopal moderator for Teens Encounter Christ movement, having held this position since 1991. Schwietz was awarded an Honorary Doctor of Humanities degree from Lewis University in 1998.
