Famous Pre Reformation Christian Pastors (Non Catholic)

After the Splintering of the Protestant Revolt, there have been many men who are famous as Pastors and Preachers even up to the present day, the Billy Grahams the Joel Olstiens, John McArthurs, an Ellen G. White and so on. My questions is, are there any famous Biblical Pastors before the 15th century that were not Catholic or Catholic-Orthodox priests or bishops or members of the Catholic or Catholic Orthodox Churches? Someone who for example, did not celebrate the traditional sacrament of the Mass?