Franz Posset is a German-American independent church historian and lay theologian in the Catholic Church. He is an internationally recognized ecumenist, specializing in the history and theology of the Renaissance and early Lutheran Reformation.
Franz was born in 1945 in Glöckelberg in the Bohemian Forest (Sudetenland), and between 1965 and 1970, he was a student of Hans Küng, Josef Ratzinger (Pope Benedict XVI emeritus), and Walter Kasper (Cardinal). He earned a diploma in Catholic theology at the University of Tübingen, and received a PhD in religious studies, with his dissertation directed by the late Kenneth Hagen at Marquette University in Milwaukee, Wisconsin.