Norman-Byzantine Wars
The Norman-Byzantine Wars were a series of conflicts during the 11th and early 12th centuries, arising from the Normans' expansion into southern Italy and Sicily and their subsequent ambitions against the Byzantine Empire. Led by Robert Guiscard, the Normans initially conquered significant territories, including the last Byzantine stronghold in Italy by 1071. The political landscape shifted when Byzantine Emperor Michael VII sought alliances with the Normans, but after his downfall, Robert Guiscard used the opportunity to assert dominance over the empire.
The wars featured key battles, including the initial Norman siege of Dyrrachium in 1081, where Robert’s forces faced resistance from Byzantine Emperor Alexius I Comnenus, who was attempting to rally support against the invaders. Despite early Norman victories, the campaigns were complicated by logistical challenges, internal strife, and the strategic maneuvers of Alexius, who sought to undermine Norman efforts. The conflict ultimately led to a Treaty of Devol in 1108, which recognized Norman Bohemund as a vassal to the Byzantine emperor for territories in the Near East, consolidating Byzantine control in the Balkans and temporarily curtailing further Norman invasions.
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Norman-Byzantine Wars
At issue: Defense of Byzantine Empire against conquest by southern Italian Normans
Date: May, 1081-autumn, 1085; autumn, 1107-September, 1108
Location: Southwestern Byzantine Empire (Albania and Greece)
Combatants: Normans vs. Byzantines and Venetians
Principal commanders:Norman, Robert Guiscard, duke of Apulia (c. 1015–1085), Bohemund, prince of Antioch (c. 1050/1058–1111); Byzantine, Emperor Alexius I Comnenus (1048–1118)
Principal battles: First Siege of Dyrrachium, Siege of Larissa, Corfu, Second Siege of Dyrrachium
Result: Normans beaten in both wars; Byzantine autonomy preserved
Background
Adventurers from Normandy began the conquest of southern Italy and Sicily in the first half of the eleventh century. Norman Robert Guiscard, also known as Robert de Hauteville, emerged as the leader on the mainland. Along with Arab and Lombard land, in 1071, the last Byzantine holding in Italy fell to the Normans. Byzantine emperor Michael VII courted Robert with honors and offices, and Robert sent his daughter to marry Michael’s infant son and heir. When Michael fell from power in 1078, Helen wound up in a monastery. Robert used this insult as an excuse to extend his power over the Byzantine Empire itself. After the Battle of Manzikert in 1071, Byzantine power had weakened in both the east and west. Held up by rebellious vassals, Robert delayed attacking the Byzantines until early 1081. By then, Alexius I Comnenus had seized the throne and begun a tentative defense.
Action
Robert’s son Bohemund, also known as Bohémond, led a vanguard across the Adriatic. Shortly thereafter, in May, 1081, Robert’s main fleet and army of 1,300 knights and thousands of infantry, arrived at Valona (Vlon) in modern Albania. The fleet proceeded to seize Corfu to the south, and the army to the north took Dyrrachium, the main port of Byzantine Illyria. Alexius had bargained with the Venetians for use of a fleet, and Venetian Doge Domenico Selva led it against the Norman fleet off of Dyrrachium. The victorious Venetians took Dyrrachium, and the Normans besieged it. Alexius arrived with a weak army of primarily mercenaries—including Anglo-Saxon Varangian guardsmen who hated the Normans—and suffered defeat at the hands of Robert, his warrior-wife Sichelgaita, and Bohemund on October 18, 1081. Dyrrachium held out until betrayed by a treacherous Venetian resident in February, 1082. Dyrrachium was at the western end of the Roman Via Egnatia, which linked the Adriatic Sea with Constantinople, and the Normans followed this across Illyria and Thessaly.
Meanwhile, Alexius was raising trouble in Robert’s rear by rousing Norman nobles to rebel and the German king Henry IV to pressure the pope and the Norman state. He also seized Orthodox Church plates and treasures and had them melted down to finance a new army, which proved ineffective at first but successfully raised the Norman Siege of Larissa in the summer of 1083. Robert had returned to Italy in April, and now Bohemund was forced to retreat to Kastoria with an unpaid, dispirited, homesick army. Alexius’s offers of bounties to men who would desert helped the Norman army melt away. When Bohemund returned to Italy to raise needed funds, his followers surrendered. Venetians quickly retook Dyrrachium and Corfu.
Robert returned, however, with 150 ships, outfoxed a Venetian fleet, and landed on Corfu (autumn, 1084), where he wintered. Typhus broke out, killing and incapacitating many Normans. Robert tried to join his son Roger in an attack on Cephallonia but died en route. Further progress was halted by bickering over inheritance.
Bohemund, prince of Antioch after the First Crusade, resumed the attack on the Byzantine Empire in 1107, arranging support from both English Henry I and French Philip I. In autumn, the Normans landed at Valona and proceeded to Dyrrachium, which they besieged until September, 1108. Famine, malaria, a blockading Venetian fleet, and the appearance of Alexius with an army broke the siege, and Bohemund signed the Treaty of Devol (1108).
Aftermath
The treaty formally recognized Bohemund as Alexius’s vassal for Antioch and other Near Eastern territories. The Byzantine hold on the Balkans was strengthened, and further Italian invasions put off for forty years.
Bibliography
Norwich, John Julian. The Normans in Sicily. London: Penguin, 1992.
Sewter, E. R. A. The Alexiad of Anna Comnena. New York: Penguin, 1969.
Treadgold, Warren. The History of the Byzantine State and Society. Stanford, Calif.: Stanford University Press, 1999.