Trial of Martin Luther over his teachings begins during the assembly of the Diet of Worms. Initially intimidated, he asks for time to reflect before answering and is given a stay of one day.

Martin Luther was a German priest, theologian, author, hymnwriter, professor, and former Augustinian friar. Luther was the seminal figure of the Protestant Reformation, and his theological beliefs form the basis of Lutheranism. He is widely regarded as one of the most influential figures in Western and Christian history.

Lutheranism is a major branch of Protestantism that emerged under the work of Martin Luther, the 16th-century German friar and reformer whose efforts to reform the theology and practices of the Catholic Church launched the Reformation in 1517. The Lutheran Churches adhere to the Bible and the Ecumenical Creeds, with Lutheran doctrine being explicated in the Book of Concord. Lutherans hold themselves to be in continuity with the apostolic church and affirm the writings of the Church Fathers and the first four ecumenical councils.

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 the views that had been criticized 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 Reformation is usually considered to have begun in 1517, this edict is the first overt schism associated with it.