Diet of Worms
The Diet of Worms of 1521 was an imperial diet of the Holy Roman Empire called by Emperor Charles V and conducted in the Imperial Free City of Worms. Martin Luther was summoned to the Diet in order to renounce or reaffirm his views in response to a Papal bull of Pope Leo X. In answer to questioning, he defended these views and refused to recant them. At the end of the Diet, the Emperor issued the Edict of Worms, a decree which condemned Luther as "a notorious heretic" and banned citizens of the Empire from propagating his ideas. Although the Protestant Reformation is usually considered to have begun in 1517, the edict signals the first overt schism.