The German Peasants' War was a widespread popular revolt in some German-speaking areas in Central Europe from 1524 to 1525. Like the preceding Bundschuh movement and the Hussite Wars, the war consisted of a series of both economic and religious revolts in which peasants and farmers, often supported by Anabaptist clergy, took the lead. It failed because of intense opposition from the aristocracy, who slaughtered up to 100,000 of the 300,000 poorly armed peasants and farmers. The survivors were fined and achieved few, if any, of their goals. The German Peasants' War was Europe's largest and most widespread popular uprising before the French Revolution of 1789. The fighting was at its height in the middle of 1525.

In mounting their insurrection, peasants faced insurmountable obstacles. The democratic nature of their movement left them without a command structure and they lacked artillery and cavalry. Most of them had little, if any, military experience. Their opposition had experienced military leaders, well-equipped and disciplined armies, and ample funding.

The revolt incorporated some principles and rhetoric from the emerging Protestant Reformation, through which the peasants sought influence and freedom. Radical Reformers and Anabaptists, most famously Thomas Müntzer, instigated and supported the revolt. In contrast, Martin Luther and other Magisterial Reformers condemned it and clearly sided with the nobles. In Against the Murderous, Thieving Hordes of Peasants, Luther condemned the violence as the devil's work and called for the nobles to put down the rebels like mad dogs. The movement was also supported by Ulrich Zwingli, but the condemnation by Martin Luther contributed to its defeat.