Key Facts
- Duration
- November 1107 – September 1108
- Attacker
- Bohemond I of Antioch (Italo-Normans)
- Defender
- Byzantine Empire, doux Alexios Komnenos
- Result
- Treaty of Devol; Antioch became Byzantine vassal
- Primary source
- Alexiad of Anna Komnene
Strategic Narrative Overview
Rather than risk another open battle, Emperor Alexios I adopted a strategy of attrition. He dispatched forces to seize mountain passes in the Normans' rear, cutting off their foraging and supplies. Byzantine commanders also spread disease in the Norman camp and deployed Greek fire to destroy their siege engines. These measures steadily eroded Norman strength and morale without committing imperial forces to a decisive pitched engagement.
01 / The Origins
Bohemond I of Antioch launched an Italo-Norman expedition across the Adriatic to seize Dyrrhachium, a strategic Byzantine port on the eastern Adriatic coast. His campaign echoed an earlier Norman assault on the same city in 1081, when Emperor Alexios I Komnenos had been heavily defeated trying to relieve it. Control of Dyrrhachium offered a gateway into Byzantine territory and a platform for further Norman expansion into the Balkans.
03 / The Outcome
Weakened by disease, supply shortages, and the destruction of their siege equipment, the Normans could not take the city. Bohemond sought terms and negotiated the Treaty of Devol in 1108, by which he acknowledged Byzantine suzerainty and the Principality of Antioch became a Byzantine vassal state. The treaty effectively ended the Norman threat to Byzantine possessions in the Adriatic and the Balkans.
Belligerents & Mobilization Analysis
Side A
1 belligerent
Bohemond I of Antioch.
Side B
1 belligerent
Alexios I Komnenos, Alexios Komnenos (doux of Dyrrhachium).
Kinetic Engagement Axis
Scroll horizontally to view full axis. Events plotted relatively.