The shattering of Western Christianity's religious unity. Martin Luther and the birth of Protestantism, the spread and diversification of reform movements, the Catholic Counter-Reformation, and the religious wars that reshaped Europe's political map.
Church corruption, the sale of indulgences, and Christian humanist critiques that set the stage for reform.
Topic 2.2
Martin Luther & Lutheranism
The 95 Theses, justification by faith alone, and the Diet of Worms.
Topic 2.3
The Spread & Diversification of Protestantism
Zwingli, Calvin's Geneva, the Anabaptists, and the English Reformation under Henry VIII and Elizabeth I.
Topic 2.4
The Catholic Counter-Reformation
The Council of Trent, the Jesuits, and Ignatius Loyola's program of Catholic renewal.
Topic 2.5
Religious Wars & Conflict
The Peace of Augsburg, the French Wars of Religion, the Dutch Revolt, and the roots of the Thirty Years' War.
Topic 2.6
Social & Economic Effects of the Reformation
Witch hunts, changing family and gender roles, and how print culture spread reform ideas.
About Unit 2
Unit 2 traces how Martin Luther's challenge to Church authority in 1517 grew into a permanent fracture of Western Christianity. You'll see how Lutheranism's call for justification by faith alone splintered further into Calvinism, the Anabaptist movement, and the English Reformation — each with its own theology and political consequences. The Catholic Church responded with its own internal reform, the Counter-Reformation, anchored by the Council of Trent and the new Jesuit order.
This unit is roughly 10–13% of the AP European History exam. Its central tension — religious conviction versus political power — drove decades of conflict, from the Peace of Augsburg's compromise of "cuius regio, eius religio" to the French Wars of Religion and the opening moves of the Thirty Years' War.
The College Board ties Unit 2 to four of its course-wide themes:
CID
The Reformation fractured religious unity and reshaped intellectual authority away from the Church
SP
Rulers used religious affiliation to consolidate state power, as in cuius regio, eius religio
SOC
Reformation ideas altered social structures, including family life and gender roles
INT
Print culture allowed reform ideas to spread rapidly across Europe