Catholic Church

===Protestant Reformation and Counter-Reformation===
{{Main|Protestant Reformation|Counter-Reformation}}
{{See also|Martin Luther|Ninety-five Theses}}
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| footer = In 1517, [[Martin Luther]] (left), originally an [[Order of Saint Augustine|Augustinian]] friar, posted and published ''[[Ninety-five Theses]]'' (right), detailing Luther's opposition to what he saw as the Roman Catholic Church's abuse and corruption by Catholic clergy, including their sale of plenary indulgences, which were certificates supposed to reduce the temporal punishment in purgatory for sins committed by the purchasers or their loved ones. Luther's publication and release of the document is widely credited with launching the [[Reformation]]. 
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In 1415, [[Jan Hus]] was burned at the stake for heresy, but his reform efforts encouraged [[Martin Luther]], an [[Order of Saint Augustine|Augustinian]] friar in modern-day Germany, who [[History of Lutheranism#The start of the Reformation|sent]] his ''[[Ninety-five Theses]]'' to several bishops in 1517.{{sfn|Bokenkotter|2004|p=215}} His theses protested key points of Catholic [[doctrine]] as well as the sale of [[indulgence]]s, and along with the [[Leipzig Debate]] this led to his [[Martin Luther#Excommunication|excommunication]] in 1521.{{sfn|Bokenkotter|2004|p=215}}<ref name="Vidmar184">Vidmar, p. 184.</ref> 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]] [[list of Christian denominations|denominations]]{{sfn|Bokenkotter|2004|pp=223–224}} and also [[crypto-protestantism|crypto-Protestantism]] within the Catholic Church.<ref>{{cite journal|last=Fernández|first=Luis Martínez|title=Crypto-Protestants and Pseudo-Catholics in the Nineteenth-Century Hispanic Caribbean|journal=Journal of Ecclesiastical History|volume=51|issue=2|pages=347–365|year=2000|doi=10.1017/S0022046900004255|s2cid=162296826}}</ref> Meanwhile, [[Henry VIII]] petitioned [[Pope Clement VII]] for a [[Annulment (Catholic Church)|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]].{{sfn|Bokenkotter|2004|pp=235–237}}

The Reformation contributed to clashes between the Protestant [[Schmalkaldic League]] and the Catholic Emperor [[Charles V, Holy Roman 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.<ref name="Vidmar233"/> In France, a series of conflicts termed the [[French Wars of Religion]] was fought from 1562 to 1598 between the [[Huguenot]]s (French [[Calvinists]]) and the forces of the [[Catholic League (French)|French Catholic League]], which were backed and funded by a series of popes.<ref name="Duffy177">Duffy, ''Saints and Sinners'' (1997), pp. 177–178</ref> This ended under [[Pope Clement VIII]], who hesitantly accepted King [[Henry IV of France|Henry IV's]] 1598 [[Edict of Nantes]] granting civil and [[religious toleration]] to French Protestants.<ref name="Vidmar233">Vidmar, ''The Catholic Church Through the Ages'' (2005), p. 233</ref><ref name="Duffy177"/>

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.{{sfn|Bokenkotter|2004|pp=242–244}} 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.<ref>Maxwell, Melvin. ''Bible Truth or Church Tradition'', p. 70</ref>