Fr. Gary Caster is a priest of the Diocese of Peoria ordained December 19, 1992, at the Church of St. Pius X in Rock Island. Father Gary was born and raised in Southern California but entered seminary for the Diocese of Peoria in 1987. Central Illinois his home.

Father Gary spent nearly thirty years in the education apostolate, teaching and working as a high school chaplain at Peoria Notre Dame, directing campus ministry at Bradley University, Illinois State University and Illinois Wesleyan University. Fr. Gary founded the campus ministry program at Eureka College.

In August of 2007, Father was hired as the first Catholic priest to serve as Catholic Chaplain to Williams College in Northwestern Massachusetts. Fr. Gary returned to the Diocese of Peoria in 2019 to simply be a parish priest. He assisted the Catholic Community in Ottawa, IL for four years, when in 2023 Bishop Lou appointment him Administrator (later Pastor) of St. Ambrose, Milan and St. Patrick, Andalusia. In March of 2025, the two Churches were merged to form the parish of St. Terea of Calcutta.

Fr. Gary has written and directed shows for the Eternal Word Television Network, been a frequent guest on several of their programs, written over 250 articles, contributed to the Catholic publication, Magnificat and is the author of seven books: Mary in her own words: The Mother of God in Scripture; The Little Way of Lent; The little Way of Advent; Joseph, the Man who raised Jesus, Inspired, the Powerful Presence of the Holy Spirit, Prayer Everywhere: the Spiritual Life made simple; and The Way of Simple Love. For nearly twenty years, Father Gary led parish missions throughout the United States.

Fr. Gary enjoys golfing and fishing and is an excellent cook. Fr. Gary lives in Taylor Ridge at the rectory on the St. Patrick Campus. He loves his home in the country.