The Battle of Mühlberg was a decisive cavalry engagement that took place in Saxony, Germany in 1547. The combatants were the forces of the Holy Roman Emperor Charles I of Spain, commanded by the Duke of Alba, and the troops of the Schmalkaldic League, a defensive alliance of Protestant princes. The battle was part of the larger conflict known as the Schmalkaldic War, which stemmed from religious and political tensions arising from the Protestant Reformation.

Duke of Alba led approximately 25,000 troops, including a considerable contingent of heavy cavalry, against a smaller army of 16,000 soldiers belonging to the Schmalkaldic League, led by John Frederick I of Saxony and Philip of Hesse. The Duke’s forces executed a series of coordinated attacks that exploited weaknesses in the league’s formation, demonstrating superior military tactics. Ultimately, the Spanish-Imperial troops routed the Schmalkaldic forces, resulting in heavy casualties and significant losses in morale for the Protestant side.

The aftermath of the battle not only solidified Charles I's power in the Holy Roman Empire but also led to increased centralization of authority. The victory allowed the Emperor to impose the Augsburg Interim, a temporary peace that sought to establish religious uniformity. This battle hence acted as a turning point in the dynamics of the Reformation, underscoring the contentious struggle between Catholic and Protestant ideologies during this period.