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Table of Contents
Unit 2 Overview: Age of Reformation
2.1 Contextualizing 16th and 17th-Century Challenges and Developments
2.2 Luther and the Protestant Reformation
2.3 Protestant Reform Continues
2.4 Wars of Religion
2.5 The Catholic Reformation
2.6 16th-Century Society & Politics in Europe
2.7 Mannerism and Baroque Art
2.8 Causation in the Age of Reformation and the Wars of Religion

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2.4 Wars of Religion

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The Protestant Reformation dramatically reshaped the religious, social, and political landscape of Europe. As the Catholic Church's dominance weakened, religious conflicts intertwined with political struggles, leading to prolonged and devastating wars. While many of these wars had theological disputes at their core, political ambitions and power struggles often played an equally significant role.

Religious Conflict and Political Struggles

A recurring theme in these wars was the power struggle between the nobility and monarchy. Protestantism often found support among nobles who sought greater autonomy, while many monarchs remained Catholic, using religion to reinforce their central authority. For example:

  • In France, many nobles converted to Protestantism, challenging the Catholic monarchy.
  • In England, the monarchy itself broke away from Catholicism, establishing the Anglican Church, even as significant noble factions remained Catholic.
  • In the Holy Roman Empire, Protestant princes sought independence from the Catholic Emperor.

The German Religious Conflicts

German Peasants' War (1524–1525)

The German Peasants' War was fueled by economic hardship, feudal oppression, and religious reform. Inspired by Martin Luther’s doctrine of the priesthood of all believers, many peasants saw the Reformation as an opportunity to challenge the existing social hierarchy.

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However, Luther, fearing chaos, ultimately condemned the revolt in his pamphlet Against the Murderous, Thieving Hordes of Peasants (1525). This led to the brutal suppression of the rebellion by the nobility.

CausesOutcomes

| Crop failures and economic hardship | Peasant armies failed due to poor organization and inferior weaponry | | Desire for social equality | Nobles violently restored order | | Increased feudal rents and restrictions | Peasant rights were further curtailed | | Influence of Lutheran teachings | Strengthened the authority of German princes |

Schmalkaldic Wars (1546–1547) and the Peace of Augsburg (1555)

The Schmalkaldic Wars erupted as Protestant German princes, organized under the Schmalkaldic League, resisted the Catholic Holy Roman Emperor Charles V. Charles sought to restore Catholic control but faced strong opposition.

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The conflict ended with the Peace of Augsburg (1555), a landmark treaty allowing each German prince to determine the religion of their state—either Lutheranism or Catholicism—under the principle of Cuius regio, eius religio (Whose realm, his religion). However, the treaty failed to recognize Calvinism, setting the stage for the 30 Years War (mentioned below).

French Religious Conflicts

French Wars of Religion (1562–1598)

France was torn apart by a series of violent conflicts between Catholics and Huguenots (French Calvinists). Although Huguenots made up only about 10% of France’s population (roughly 2 million people), they comprised around 40% of the nobility, making them a political threat to the Catholic monarchy.

One of the most notorious events of this period was the St. Bartholomew’s Day Massacre (1572), in which thousands of Huguenots were killed under orders from Catherine de’ Medici, the queen mother. The war culminated in the War of the Three Henries (1585–1589), a power struggle between:

NamePositionReligious AffiliationOutcome

| Henry of Guise | Catholic nobleman | Catholic Royalist | Assassinated in 1588 | | Henry III | King of France | Catholic | Assassinated in 1589 | | Henry of Navarre (Henry IV) | Heir to the throne | Huguenot (converted to Catholicism) | Became King |

Henry of Navarre emerged victorious, becoming Henry IV of France. To unify the kingdom, he converted to Catholicism, allegedly stating, "Paris is worth a Mass."

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In 1598, he issued the Edict of Nantes, granting Huguenots limited religious freedom and marking the first significant step toward religious toleration in France.

Henry IV is often considered the first Politique—a ruler who prioritized state stability over religious conformity.

The Thirty Years' War (1618 - 1648)

PAY ATTENTION, this war essential for contextualizing the rest of the unit!

Causes of the War

The Thirty Years' War was one of the most destructive conflicts in European history, initially sparked by religious tensions but ultimately expanding into a broader political struggle. Several key factors contributed to the outbreak of war:

Religious Motives

FactorExplanation

| Peace of Augsburg (1555) | Allowed German princes to choose between Catholicism and Lutheranism in their territories under the principle of Cuius regio, eius religio (whose realm, his religion). However, it failed to accommodate Calvinism, leading to tensions. | | Calvinist Recognition | Calvinists demanded formal recognition, challenging the religious status quo within the Holy Roman Empire. |

Political Motives

FactorExplanation

| Habsburg Dominance in Europe | The Habsburgs had been a dominant force in European politics throughout the 16th century. In 1556, Emperor Charles V divided his empire between the Spanish Habsburgs (led by Philip II) and the Austrian Habsburgs (led by Ferdinand I). This division weakened Habsburg control but still maintained their influence. | | Weakening of the Spanish Habsburgs | Spain faced significant setbacks, including Dutch Revolts (1566-1581) against Catholic rule and the defeat of the Spanish Armada (1588) by Protestant England. | | Austrian Habsburg Challenges | The Austrian Habsburgs faced constant Ottoman invasions, diverting resources and attention away from internal European affairs. Meanwhile, France, under Cardinal Richelieu, sought to weaken Habsburg power. |

The Outbreak of War: The Bohemian Revolt (1618)

The Thirty Years' War began in Bohemia (modern-day Czech Republic) as a localized religious conflict before expanding across Europe.

  • In 1617, the Bohemian nobility feared that Ferdinand II, a staunch Catholic, would revoke Protestant rights.
  • In defiance, Protestant nobles elected Frederick V, a Protestant, as their ruler.
  • In response, Ferdinand II’s Catholic representatives traveled to Prague—where Protestant nobles threw them out of a 69-foot-high window! This event, known as the Defenestration of Prague, directly sparked war. (Miraculously, the representatives survived.)

What began as a Bohemian dispute quickly escalated into a broader European conflict. Protestant and Catholic states, as well as powerful monarchs, intervened for religious and political reasons.

The Four Phases of the Thirty Years' War

The war unfolded in four distinct phases, each marked by new participants and shifting motivations.

PhaseTimeframe & LocationKey PlayersMajor EventsOutcome

| Bohemian Phase | 1618-1625 (Bohemia) | Ferdinand II, Johann Tserclaes of Tilly, Frederick V, Count Ernst von Mansfeld | Defenestration of Prague → Protestant revolt against Catholic rule | Battle of White Mountain (1620): Catholic forces crushed Protestant resistance, solidifying Habsburg control. | | Danish Phase | 1625-1629 (Germany & Denmark) | Ferdinand II, Albrecht von Wallenstein, Christian IV of Denmark | Denmark, a Protestant nation, intervened to support Protestant German states | Peace of Lübeck (1629): Catholic victory; Denmark withdrew from the war. | | Swedish Phase | 1630-1635 (Germany) | Gustavus Adolphus (Sweden), Wallenstein, Cardinal Richelieu (France) | Sweden, under the skilled military leadership of Gustavus Adolphus, invaded Germany to protect Protestants and weaken the Habsburgs. | Gustavus Adolphus was killed in battle (1632), but Sweden remained involved. The war became less about religion and more about power. | | French (Franco-Swedish) Phase | 1635-1648 (Germany) | Cardinal Richelieu (France), Holy Roman Empire, Maximilian of Bavaria | France, despite being Catholic, directly joined on the Protestant side to weaken the Habsburgs. | Peace of Westphalia (1648): Ended the war and redefined European politics. |

The Peace of Westphalia (1648)

The Treaty of Westphalia fundamentally reshaped Europe by ending the Thirty Years' War and introducing new principles of state sovereignty.

Key ImpactDetails

| Religious Settlement | - Calvinism was officially recognized, alongside Catholicism and Lutheranism. - Limited papal authority in German states, reducing Catholic Church influence. |

| Habsburg Decline | - German princes gained more autonomy, further weakening the Holy Roman Emperor. - The Austrian Habsburgs retained control but lost influence over German states. |

| Rise of New Powers | - The Dutch Republic and Switzerland gained independence. - France emerged as Europe’s dominant power, while Spain declined. |

| ⭐️ Modern State System ⭐️ | - Established the principles of state sovereignty and non-intervention, marking the beginning of the modern international system. |

The Thirty Years' War devastated Germany, causing population losses of 20-40% in some regions due to war, famine, and disease. The war's conclusion marked the end of large-scale religious wars in Europe and the shift toward power-based conflicts.

Manipulative States: Exploiting Religion for Power

While religious divisions fueled much of the conflict, some rulers used religion as a political tool to consolidate power.

Spain: The Spanish Inquisition

  • Spain remained the strongest Catholic monarchy, using the Spanish Inquisition to enforce religious uniformity.
  • Under Ferdinand and Isabella, Spain expelled Jews and Muslims, forcing them to convert or leave.
  • Philip II continued persecuting Protestants in the Netherlands, leading to the Dutch Revolt.

England: Henry VIII and the English Reformation

  • Henry VIII, initially a devout Catholic, broke from the Catholic Church when the Pope refused to grant him a divorce from Catherine of Aragon.
  • He established the Church of England (Anglican Church) in 1534, making himself the Supreme Head of the church.
  • England fluctuated between Protestantism and Catholicism under his successors:
    • Edward VI (Protestant) strengthened the Anglican Church.
    • Mary I ("Bloody Mary") restored Catholicism and executed Protestants.
    • Elizabeth I re-established Protestantism, solidifying England’s religious settlement.

The Wives and Successors of Henry VIII

NameFateChildrenTitle

| Henry VIII | Died of natural causes | Edward VI, Mary I, Elizabeth I | King of England | | Catherine of Aragon | Divorced; died of illness | Mary I | First Wife | | Anne Boleyn | Executed | Elizabeth I | Second Wife | | Jane Seymour | Died in childbirth | Edward VI | Third Wife | | Anne of Cleves | Divorced; died of cancer | None | Fourth Wife | | Catherine Howard | Executed | None | Fifth Wife | | Catherine Parr | Died in childbirth | None | Sixth Wife | | Edward VI | Died young (tuberculosis) | None | King of England | | Lady Jane Grey | Executed | None | Queen of England (9 days) | | Mary I | Died of illness | None | Queen of England | | Elizabeth I | Died of sepsis | None | Queen of England |

The End of an Era

==By the mid-17th century, it was clear that a unified Catholic Europe was no longer possible. Religious pluralism became a permanent feature of European life, shaping future political and social structures.==

Even in nations like Poland and the Netherlands, where Catholicism remained dominant, Protestants were tolerated, reflecting the new reality of religious diversity.

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The religious wars of the 16th and 17th centuries ended with political pragmatism replacing religious zeal—ushering in the era of state-driven diplomacy and balance-of-power politics.

🎥 Watch: AP European History - Thirty Years’ War 🎥.

🎥 Watch: AP European History - Martin Luther and Reformation

🎥 Watch: AP European History - French Wars of Religion

Key Terms to Review (18)

Bohemia: Bohemia was a historical region in central Europe, primarily located in what is now the Czech Republic. During the Wars of Religion, it became a focal point of conflict between Catholic and Protestant factions, most notably during the Thirty Years' War, which had profound implications for European politics and religion.
Charles V: Charles V was the Holy Roman Emperor from 1519 to 1556 and King of Spain from 1516, representing one of the most significant political figures in European history during the 16th century. He ruled over an extensive empire that included vast territories in Europe and the Americas, which made him a central figure during critical conflicts such as the Protestant Reformation and the Wars of Religion.
Diet of Worms: The Diet of Worms was an imperial council held in 1521, convened by Holy Roman Emperor Charles V to address the growing concerns regarding Martin Luther's teachings and the Protestant Reformation. This assembly marked a pivotal moment in religious and political history, as it culminated in Luther's refusal to recant his 95 Theses and other writings, thereby solidifying the divide between the Catholic Church and emerging Protestant beliefs.
Edict of Nantes: The Edict of Nantes was a decree issued in 1598 by King Henry IV of France, granting religious tolerance to Huguenots (French Protestants) and ending the religious wars between Catholics and Protestants in France. This edict was significant in establishing a framework for coexistence between the two groups, reflecting the broader context of political and religious conflicts in Europe during this period.
Ferdinand II: Ferdinand II was the Holy Roman Emperor from 1619 until his death in 1637, known for his role in the Thirty Years' War and as a staunch supporter of Catholicism during a period marked by intense religious conflict. His reign saw the escalation of hostilities between Protestant and Catholic states in Europe, contributing to a broader struggle for power and influence that defined the Wars of Religion.
French Wars of Religion: The French Wars of Religion were a series of conflicts from 1562 to 1598 primarily between French Catholics and Huguenots (French Protestants), marked by political struggles for power and religious dominance. These wars are crucial in understanding the broader context of religious conflicts in Europe during the Reformation and their impact on state power, society, and politics.
German Peasants' War: The German Peasants' War was a widespread revolt in the early 16th century, occurring between 1524 and 1525, where peasants in the Holy Roman Empire sought to improve their living conditions and gain rights against oppressive landlords. This uprising was significant as it reflected the social tensions and economic grievances that arose during the Reformation, leading to a violent conflict between the peasantry and the ruling authorities.
Habsburgs: The Habsburgs were a prominent royal family that rose to power in Europe during the late Middle Ages and continued to influence European politics until the early 20th century. They ruled over a vast empire, which included territories in modern-day Austria, Spain, the Netherlands, and parts of Italy, and played a central role in the religious conflicts and political struggles during the Wars of Religion.
Henry of Navarre: Henry of Navarre, also known as Henry IV of France, was a pivotal figure during the Wars of Religion in France, reigning from 1589 until his assassination in 1610. He was a Protestant leader who became king after the War of the Three Henrys and ultimately converted to Catholicism to secure his rule and end the religious conflicts that plagued France. His ascension marked a significant turning point, as he worked to promote tolerance and stabilize the nation.
Holy Roman Empire: The Holy Roman Empire was a multi-ethnic complex of territories in central Europe that existed from the early Middle Ages until 1806, characterized by a decentralized political structure and the symbolic authority of the emperor. This empire played a critical role in European politics, influencing the rise of new monarchies, the wars of religion, state building efforts, and the balance of power in Europe.
King Henry IV: King Henry IV was the first French monarch of the House of Bourbon, reigning from 1589 until his assassination in 1610. His reign marked a significant turning point in France, as he worked to unify a nation divided by religious conflicts and established the foundations for a stronger centralized monarchy.
Martin Luther: Martin Luther was a German theologian and religious reformer whose actions sparked the Protestant Reformation in the 16th century. He challenged the Catholic Church's practices, especially the sale of indulgences, and emphasized salvation through faith alone, reshaping the religious landscape of Europe.
Ottoman Empire: The Ottoman Empire was a powerful Islamic state that lasted from the late 13th century until the early 20th century, covering parts of Southeastern Europe, Western Asia, and North Africa. It was known for its vast territorial reach and cultural diversity, significantly influencing European politics and society during its height.
Peace of Augsburg: The Peace of Augsburg was a treaty signed in 1555 that ended the religious civil war between Catholics and Protestants in the Holy Roman Empire. This agreement allowed each prince to determine whether their territory would be Catholic or Lutheran, thereby establishing a precedent for religious self-determination in the region and reflecting the broader religious conflicts of the time.
Schmalkaldic Wars: The Schmalkaldic Wars were a series of conflicts between Protestant princes in the Holy Roman Empire and the Catholic emperor Charles V, primarily occurring from 1546 to 1555. These wars were significant as they represented a critical struggle during the Protestant Reformation, highlighting the tensions between Protestant reformers and traditional Catholic authority.
Schmalkaldic League: The Schmalkaldic League was a defensive alliance formed in 1531 by Protestant territories within the Holy Roman Empire to protect their interests against the Catholic Emperor Charles V. This league played a crucial role during the Wars of Religion, representing the organized resistance of Protestant states against Catholic dominance and imperial authority.
The Thirty Years' War: The Thirty Years' War was a devastating conflict in Europe from 1618 to 1648, primarily fought within the Holy Roman Empire, involving numerous European powers. It began as a struggle between Catholic and Protestant states but evolved into a broader political struggle, impacting the continent's balance of power, religion, and society.
95 Theses: The 95 Theses were a list of propositions for debate written by Martin Luther in 1517 that criticized the practices of the Catholic Church, particularly the sale of indulgences. This document is often seen as the catalyst for the Protestant Reformation, as it sparked widespread debate and led to significant religious and political changes across Europe.