Battle of Mühlberg (1547): Charles V Defeats the Lutheran Princes

The Battle of Mühlberg was fought on 24 April 1547 near the town of Mühlberg on the river Elbe in Saxony, where Emperor Charles V defeated the army of the Protestant Schmalkaldic League. The imperial forces forded the river in the morning mist and routed the Saxons, capturing their leader, Elector John Frederick I. It was the high point of Charles’s power in Germany, celebrated in Titian’s famous equestrian portrait.

Background: the Schmalkaldic League

After the Lutheran princes presented the Augsburg Confession in 1530, the emperor demanded their return to the Catholic Church. In response, Lutheran rulers and cities formed a defensive alliance at Schmalkalden in 1531, led by Elector John Frederick of Saxony and Landgrave Philip of Hesse.

For fifteen years Charles was too busy with France and the Ottoman Empire to confront them. By 1546, after making peace with France at Crépy (1544) and arranging a truce with the Ottomans, he was free to act. Martin Luther died in February 1546, and that summer war broke out.

Charles presented the campaign as punishment of rebellious princes rather than a war of religion. He also won over Duke Maurice of Saxony, a Lutheran from the rival Albertine branch of the Saxon dynasty, by promising him his cousin John Frederick’s electoral title.

The battle

The war went slowly in 1546, but in the spring of 1547 Charles marched into Saxony. John Frederick, whose army was smaller and divided, retreated along the east bank of the Elbe, believing the river would protect him.

On the morning of 24 April, imperial troops found a ford near Mühlberg. Spanish soldiers swam across to seize boats, and the cavalry, followed by the emperor himself, crossed under cover of mist. The Saxons, caught on the march, fell back towards Wittenberg and were overtaken on the heath near Falkenberg.

Their army broke and fled. John Frederick was wounded in the face and captured. Figures for losses are uncertain, but Saxon casualties are usually put in the low thousands, while imperial losses were light. A famous phrase attributed to Charles adapts Caesar: “I came, I saw, and God conquered.”

Consequences

By the Capitulation of Wittenberg in May 1547, John Frederick surrendered the electoral dignity and much of his territory to Maurice, who was formally invested as elector in 1548. Philip of Hesse submitted in June 1547 and was detained. Both princes remained prisoners for about five years.

Charles entered Wittenberg, the birthplace of the Lutheran Reformation, after its surrender. A well-known story, recorded in later tradition rather than firm contemporary evidence, says that he refused advice to dig up Luther’s body, remarking that he made war on the living, not the dead. Whatever the truth, Luther’s grave in the Castle Church was left undisturbed.

At the “armoured” Diet of Augsburg in 1548, Charles imposed the Augsburg Interim, a temporary religious settlement that allowed Protestants only a few concessions, such as married clergy and communion in both kinds. It was widely resisted.

The victory proved short-lived. In 1552 Maurice of Saxony turned against Charles, allied with France and nearly captured the emperor at Innsbruck. The Treaty of Passau that year released the prisoners, and the Peace of Augsburg in 1555 recognised Lutheranism in the Empire.

Key people

• Charles V (1500–1558), Holy Roman Emperor and King of Spain, who led the army in person despite suffering from gout.
• Fernando Álvarez de Toledo, Duke of Alba, the emperor’s commander, later notorious as governor of the Netherlands.
• John Frederick I of Saxony (1503–1554), Elector and leader of the Schmalkaldic League, nicknamed “the Magnanimous”.
• Maurice of Saxony (1521–1553), the Lutheran duke who sided with Charles in 1546–1547 and turned against him in 1552.
• Philip of Hesse (1504–1567), co-leader of the League, who surrendered after the battle.

Titian’s portrait

In 1548 Titian painted Charles at Augsburg in the armour he had worn at Mühlberg, riding alone across a twilit landscape with a lance. The painting, now in the Prado, avoids any scene of battle and presents the emperor as a calm Christian knight. It became a model for equestrian royal portraits by later painters such as Rubens and Velázquez.

Timeline

• 1531, February: The Schmalkaldic League is formed.
• 1546, 18 February: Martin Luther dies in Eisleben.
• 1546, July: The Schmalkaldic War begins.
• 1547, 24 April: Imperial forces win at Mühlberg; John Frederick is captured.
• 1547, 19 May: Capitulation of Wittenberg.
• 1547, June: Philip of Hesse submits to the emperor.
• 1548: Titian paints Charles V at Mühlberg; the Augsburg Interim is issued.
• 1552: Princes’ revolt and Treaty of Passau.

Why it matters

Mühlberg showed that military victory could not undo the Reformation in Germany. Within a few years the defeated cause had regained its ground, and the compromise of 1555 accepted religious division. For Charles V, the battle was both his greatest triumph and the start of the setbacks that led to his abdication.