Bishop Robert Gruss was born June 25, 1955, in Texarkana, Arkansas. He attended Madison Area Technical College, in Madison, Wisconsin, and Spartan School of Aeronautics in Tulsa, Oklahoma, and was a corporate pilot and flight instructor from 1980-1989 before entering seminary. He pursued seminary studies at St. Ambrose University, in Davenport 1989-1990; at North American College, Rome, 1990-1994; and the Pontifical University of St. Thomas Aquinas, also known as the Angelicum, in Rome. He additionally earned a Master of Arts degree in Spiritual Theology at the University of St. Thomas Aquinas in 1994. In 1999, he completed studies at the Institute of Priestly Formation (IPF) with an emphasis on Spiritual Direction training.
Bishop Gruss was ordained to the priesthood on July 2, 1994 by Bishop William E. Franklin, seventh Bishop of Davenport. In 2007, Pope Benedict named him a Chaplain of his Holiness, giving him the title of monsignor. He was appointed by Pope Benedict XVI as Bishop of Rapid City in 2011 and consecrated as a bishop on July 28, 2011.
His previous assignments have included chancellor and diocesan vocations director for the Diocese of Davenport, as well as pastor at Sacred Heart Cathedral. He also served as vice-rector at the Pontifical North American College in Rome.
Bishop Gruss also serves in the following capacities: St. Ambrose University Corporate Board, Member; Catholic Radio Association Episcopal Board, Member; Pope Leo XIII Institute, Episcopal Moderator; Institute for Priestly Formation Bishops Advisory Council, Member; National Assn. of Catholic Chaplains, Reg. VIII Episcopal Rep.; Pontifical North American College Episcopal Board of Governors.