section_path: History/Protestant Reformation and Counter-Reformation
section_name: Protestant Reformation and Counter-Reformation
paragraph_text: Protestant Reformation and Counter-Reformation
  
  In 1415, Jan Hus was burned at the stake for heresy, but his reform efforts encouraged Martin Luther, an Augustinian friar in modern-day Germany, who sent his Ninety-five Theses to several bishops in 1517. His theses protested key points of Catholic doctrine as well as the sale of indulgences, and along with the Leipzig Debate this led to his excommunication in 1521. In Switzerland, Huldrych Zwingli, John Calvin and other Protestant Reformers further criticized Catholic teachings. These challenges developed into the Reformation, which gave birth to the great majority of Protestant denominations and also crypto-Protestantism within the Catholic Church. Meanwhile, Henry VIII petitioned Pope Clement VII for a declaration of nullity concerning his marriage to Catherine of Aragon. When this was denied, he had the Acts of Supremacy passed to make himself Supreme Head of the Church of England, spurring the English Reformation and the eventual development of Anglicanism.
  
  The Reformation contributed to clashes between the Protestant Schmalkaldic League and the Catholic Emperor Charles V and his allies. The first nine-year war ended in 1555 with the Peace of Augsburg but continued tensions produced a far graver conflict—the Thirty Years' War —which broke out in 1618. In France, a series of conflicts termed the French Wars of Religion was fought from 1562 to 1598 between the Huguenots (French Calvinists) and the forces of the French Catholic League, which were backed and funded by a series of popes. This ended under Pope Clement VIII, who hesitantly accepted King Henry IV's 1598 Edict of Nantes granting civil and religious toleration to French Protestants.
  
  The Council of Trent (1545–1563) became the driving force behind the Counter-Reformation in response to the Protestant movement. Doctrinally, it reaffirmed central Catholic teachings such as transubstantiation and the requirement for love and hope as well as faith to attain salvation. In subsequent centuries, Catholicism spread widely across the world, in part through missionaries and imperialism, although its hold on European populations declined due to the growth of religious scepticism during and after the Enlightenment.