The Battle of Pavia, fought on the morning of 24 February 1525, was the decisive engagement of the Italian War of 1521–26 between the Kingdom of France and the Habsburg Empire of Charles V, Holy Roman Emperor as well as ruler of Spain, Austria, the Low Countries, and the Two Sicilies.
The French army was led by King Francis I of France, who laid siege to the city of Pavia (then part of the Duchy of Milan within the Holy Roman Empire) with 26,200 troops since the month of October. The French infantry consisted of 6,000 French soldiers and 17,000 foreigners: 8,000 Swiss mercenaries, and 9,000 German-Italian black bands. The French cavalry consisted of 2,000 knights and 1,200 lances fournies. Charles V sent a relief force of 22,300 troops under the nominal command of the Flemish Charles de Lannoy, the captain of the Imperial army and viceroy of Naples, in order to break the siege. The Habsburg infantry consisted of 12,000 German Landsknechte, 5,000 Spaniards, and 3,000 Italians. Actual command of the infantry was exercised by an Italian Condottiero, the Marquis of Pescara, in conjunction with the German military leader Georg Frundsberg and the Spanish captain Antonio de Leyva who was in charge of an Imperial garrison inside Pavia. The cavalry, led by Lannoy and the French Duke of Bourbon (who had changed side in favor of Charles V during the war), consisted of 1,500 knights and 800 lances.
The battle was fought in the Visconti Park of Mirabello di Pavia, outside the city walls, where Pescara and Frundsberg stationed their forces in pike and shot formation. Francis took a personal initiative and led a cavalry charge against Lannoy, with the possible intent of capturing Bourbon, but it was held by German and Spanish pikemen and pummeled by arquebus fire. The arquebusiers formed a part of the Spanish colunellas and the German doppelsöldner. A mass of Spanish and German foot soldiers descended on the French cavalry from all sides and initiated to systematically kill the French gendarmes. The remaining French forces, including Swiss mercenaries and Black bands, intervened to protect the King but were surrounded by the pikemen in front of them and by the defensive forces of Pavia that made a sortie behind them.
In the four-hour battle, the French army was split and defeated in detail. Many of the chief nobles of France were killed or captured. In the chaos of the battle, Francis fell from his horse and found himself surrounded by Germans and Spaniards. Two followers of the Duke of Bourbon persuaded Francis to surrender to Charles de Lannoy, who kneeled before the King and made him a prisoner.
By 8:00 am, a mass of Imperial pikemen and arquebusiers descended on the French cavalry from all sides. Lacking room to maneuver because of the surrounding woods, the French gendarmes were surrounded and systematically killed. Richard de la Pole and Lorraine, advancing to assist Francis, were met by Frundsberg’s arriving landsknechts; the French infantry was broken and routed, and de la Pole and Lorraine were both killed. In a particularly bitter contest between Imperial and freelance landsknechts, the Black Band was surrounded by Frundsberg’s pikemen and exterminated where it stood. The French king fought on as his horse was killed under him by Cesare Hercolani, an Italian Condottiere; surrounded by Spanish arquebusiers and German Landsknecht, he was taken prisoner and escorted from the field.
Meanwhile, Antonio de Leyva had sortied with the garrison, overrunning the 3,000 Swiss under Montmorency that had been manning the siege lines. The remnants of the Swiss–both Montmorency’s and Flourance’s—tried to flee across the river, suffering massive casualties as they did. The French rearguard, under the Duke of Alençon, had taken no part in the battle; when the Duke realized what had occurred in the park, he quickly began to retreat towards Milan. By 9:00 am, the battle was over.
Francis was imprisoned in the Imperial tower of Pizzighettone, and then transferred to a fortress in Spain where he signed the Treaty of Madrid (1526) with Charles V. By the terms of the treaty, France ceded Burgundy to the Habsburg Netherlands and abandoned the Imperial Duchy of Milan. The outcome of the battle cemented Habsburg ascendancy in Italy and Europe, although Francis denounced the treaty after his liberation and re-opened hostilities over Burgundy and Lombardy shortly after.