Original: Origins of the war The Peace of Augsburg (1555), signed by Charles V, Holy Roman Emperor, confirmed the result of the 1526 Diet of Speyer, ending war between German Lutherans and Catholics.
Simplified: First, The Peace of Augsburg (1555), which was signed quickly by Charles V, agreed with the 1526 Diet of Worms and stopped the fighting between the Lutherans and the Catholics in Germany.