The Diet of Worms was a conference in 1521 (from 27 Jan. to 25 May) to which Martin Luther (1483–1546), the founder of the German Reformation, was summoned to defend his doctrines before emperor Charles V (1500–1558).

Charles V was elected emperor in 1519 and ruled over the Netherlands, Spain, Naples, and the county of Burgundy. He soon experienced challenges because of the growth of Lutheranism. Luther’s teachings were earlier condemned by Pope Leo X (1475–1521), but he refused to retract them.

The Diet of Worms was one of the most important confrontations of the early Reformation. Early tradition asserts that Luther concluded his answer with the words, “Here I stand. I can do no other. God help me. Amen.” Immediately following the Diet, Luther was formally condemned in the Edict of Worms and declared an “outlaw” by the papacy.