On this day in 1517, Martin Luther posted a proposal at the doors of a church in Wittenberg, Germany to debate the doctrine and practice of indulgences. This proposal is popularly known as the 95 Theses, which he nailed to the Castle Church doors. This was not an act of defiance or provocation as is sometimes thought. Since the Castle Church faced Wittenberg's main thoroughfare, the church door functioned as a public bulletin board and was therefore the logical place for posting important notices. Also, the theses were written in Latin, the language of the church, and not in the vernacular. Nonetheless, the event created a controversy between Luther and those allied with the Pope over a variety of doctrines and practices. When Luther and his supporters were excommunicated in 1520, the Luth