Siege of Pavia (773–774)

Lore & Background

Charlemagne marched his troops into Italy in early summer 773 with an army of 10,000–40,000 troops. He divided the force, giving command of one half to his uncle Bernard, son of Charles Martel. Charlemagne led his half through the Dora Susa pass near Mont Cenis, while Bernard took the Great St Bernard Pass. At the foot of the mountains, Charlemagne's army encountered Lombard fortifications but found an alternate route via scouting forces. A cavalcade attacked the defenders from the flank, and with Bernard's forces approaching from the east, the Lombards fled to fortified Pavia. The Franks began the siege by September, using attrition tactics and rudimentary engines. The Lombards suffered starvation and disease. Desiderius remained in Pavia, while his son Adelchis fled to Constantinople. Charles subdued the region around Pavia and visited the pope in Rome at Easter. In the tenth month, Desiderius surrendered in June 774.

Reader's Guide

The Siege of Pavia was a decisive event in early medieval European history. By defeating the Lombards, Charlemagne eliminated the primary threat to papal security in Italy and laid the groundwork for what would later be called the Holy Roman Empire. After the victory, Charlemagne declared himself rex Langobardorum, becoming 'King of the Franks and Lombards'—a unique act among Germanic kingdoms of the Early Middle Ages. This conquest allowed Charlemagne to forge an empire proper and ally closely with the Church as its protector. His recognition of temporal papal authority in central Italy helped establish medieval Papal power. The decline of the Lombard state was swift, and many Franks entered positions of power in Italy, though many Lombards retained their positions by making peace with Charlemagne. The memory of the siege persisted in Pavia for centuries, as seen in later frescoes and legends that altered the outcome to emphasize local identity.

Did You Know?

• Charlemagne's army numbered between 10,000 and 40,000 troops.
• The siege lasted ten months, ending in June 774.
• Desiderius' son Adelchis fled to Constantinople after Charlemagne besieged Verona.
• A later fresco in the church of San Teodoro in Pavia depicts Saint Theodore flooding the Frankish camp, altering the historical outcome.

The Collapse of a Fragile Alliance

Charlemagne's relationship with the Lombard kingdom had always been precarious. In 768, he shared the Frankish throne with his brother Carloman while simultaneously maintaining a dynastic bond to King Desiderius through his marriage to Desiderata, one of Desiderius's daughters. Yet within a year of that union, Charles repudiated the marriage, sending his wife back to her father—an act the Lombards interpreted as a grave personal insult. The situation deteriorated further after Carloman died in 771. His wife Gerberge fled the Frankish realm with their children and sought shelter at Desiderius's court in Pavia. Desiderius, returning the insult, granted her asylum and demanded that her children receive their inheritance in the Frankish kingdom. Simultaneously, the papacy found itself under direct threat: in 772, Pope Hadrian I had expelled Lombard officials from the papal curia, prompting Desiderius to invade papal lands and seize Otriculum, barely a day's march from Rome. Hadrian dispatched an embassy that traveled from Marseille to Thionville, pleading with Charlemagne to intervene before Rome itself fell. Convinced of the genuine danger to both the papacy and his own realm, Charles assembled his forces and marched toward Italy in the early summer of 773.

Two Armies Through the Alps

Rather than committing his entire force down a single mountain route, Charles split his army—numbering somewhere between ten and forty thousand men—into two columns. He personally led one half through the Dora Susa valley near Mont Cenis, while his uncle Bernard, son of Charles Martel, took the other through the Great St Bernard Pass. At the base of the mountains, the Lombards had erected fortifications to block the Frankish advance, but scouting parties discovered an alternate path. A cavalry detachment struck the defenders from the flank while Bernard's column closed in from the east, scattering the Lombard field force and driving them back behind the walls of fortified Pavia. By September, the Franks had established their siege lines. Though the Frankish army was renowned for its cavalry, Charles adopted a methodical attrition strategy against the heavily walled city, employing rudimentary siege engines and constructing both vallation and contra-vallation works to encircle the position for a prolonged campaign. Cut off from resupply with the surrounding countryside firmly in Frankish hands, the garrison within Pavia slowly succumbed to starvation and disease, while no Lombard duke or count mounted a relief effort and Desiderius never launched a decisive counterattack.

A New King, A New Order

When the tenth month of starvation finally broke Desiderius's resolve, the former Lombard king opened the gates of Pavia on a Tuesday in June 774 and surrendered to Charles. In the aftermath, Charlemagne performed an act without precedent among the Germanic kingdoms of the Early Middle Ages: he had himself proclaimed rex Langobardorum, absorbing the title of the conquered dynasty into his own. From that point forward, he styled himself King of the Franks and Lombards, a formulation that signaled something far more ambitious than mere territorial annexation. He was forging what modern historians would recognize as a true empire, and he did so in deliberate alliance with the Roman Church as its spiritual protector. His formal recognition of temporal papal authority over central Italian territories helped lay the groundwork for the medieval Papal state. The political reshaping of Italy was swift and profound. Frankish nobles filled positions of power throughout the peninsula, yet many Lombards who accepted Charles's rule retained their existing offices. As the military historian Paul K. Davis observed, the destruction of the Lombard monarchy removed Rome's most persistent security threat and laid the groundwork for what would become the Holy Roman Empire.

Pavia Remembers

The siege left an indelible mark on the urban identity of Pavia, where the memory of Lombard sovereignty as the city's capital defined its self-image for centuries. Physical traces endure: sections of the original first city walls still stand along via dei Mulini, silent witnesses to the encirclement. More strikingly, a later artistic tradition rewrote the siege's outcome. In 1514, the rector Giovanni Luchino Corti commissioned an anonymous Lombard painter to fresco the right aisle of the church of San Teodoro with a cycle depicting the life of Saint Theodore of Pavia. In this cycle, the holy bishop causes the waters of the Ticino to swell, flooding the Frankish camp and forcing Charlemagne to abandon the siege entirely. Commissioned during a period of intense uncertainty over the duchy of Milan's future amid the Italian wars, the altered narrative served to assert the city's autonomy, as though the Lombard kingdom had never truly fallen. A separate legend, rooted in the chronicle of Notker the Stammerer, holds that Charlemagne built the small church of Santa Sofia at Torre d'Isola in a single day during the siege to attend divine services, though a royal residence certainly existed there by the ninth century under Louis II of Italy.