On January 28, 1521, Emperor Charles V opened the Diet of Worms in Worms, Germany which lasted until May 25th. It produced the "Edict of Worms" which denouced Martin Luther. From the article:
"Diet of Worms | Germany [1521]
Diet of Worms, meeting of the Diet (assembly) of the Holy Roman Empire held at Worms, Germany, in 1521, made famous by Martin Luther’s appearance before it to respond to charges of heresy. Because of the confused political and religious situation of the time, Luther was called before the political authorities rather than before the pope or a council of the Roman Catholic Church.
Diet of Worms
In June 1520 Pope Leo X condemned 41 of Luther’s Ninety-five Theses, but he also gave Luther time to recant. In response, Luther publicly burned the papal bull and refused to renounce his propositions. He was excommunicated from the Roman Catholic Church on January 3, 1521. While the emperor should then have arrested and executed Luther, the intervention of Luther’s prince, Elector Frederick III the Wise of Saxony, led to the decision that he would appear for a hearing at the Diet under the emperor’s safe-conduct.
On April 17, 1521, Luther went before the Diet. In response to questioning, he admitted that the books displayed before the court were his, but, when asked to repudiate them, he requested time to consider the question. The next day, again before the assembled Diet, Luther refused to repudiate his works unless convinced of error by Scripture or by reason. Otherwise, he stated, his conscience was bound by the Word of God. According to tradition, he said, “Here I stand; I can do no other.” Disorder broke out at the conclusion of Luther’s refusal to recant, and the emperor dismissed the Diet for the day.
A hero to many of the Germans but a heretic to others, Luther soon left Worms and spent the next nine months in hiding in the Wartburg, near Eisenach. When it came to the question of what to do with him, the Diet remained divided. In May, after most of the rulers had left, a rump Diet headed by Emperor Charles V passed the Edict of Worms, which banned Luther’s writings and declared him a heretic and an enemy of the state. Although the Edict mandated that Luther should be captured and turned over to the emperor, it was never enforced. Nevertheless, it inhibited Luther’s travels throughout his lifetime and made him dependent on his prince for protection."