8 – Battle of Demetritzes (1185)
The Battle of Demetritzes is noteworthy because it is perhaps the last great victory achieved by the Byzantine Empire. The death of Manuel I Komnenos in 1180 would prove to be the final turning point as the empire started to crumble thereafter. The Sack of Constantinople in 1204 was practically the end, and while the empire lingered for a quarter of a millennium, it was little more than a small collection of territories and a once mighty city.
11-year old Alexios II Komnenos became emperor upon the death of his father, Manuel, but he was murdered by one of his relatives who became Andronikos I Komnenos in 1183. The Normans used the chaos to great effect as they sacked the Byzantine territory of Thessalonica in 1185. The Normans advanced towards Constantinople, and at that point, the unpopular Andronikos was murdered and replaced by his brother, Isaac II Komnenos.
Isaac was boosted by the arrival of volunteers in his fight against the Normans and was able to send thousands of reinforcements to aid the experienced general Alexios Branas. The Normans divided their army into three sections; one stayed at Thessalonica, another marched towards the Strymon River while the third part of the group marched towards Constantinople and occupied Mosynopolis.
According to twelfth-century Greek Byzantine historian, Niketas Choniates, the Normans at Mosynopolis became overconfident and were suddenly attacked and routed by the Byzantine army. Branas then took his army to deal with the Norman threat at the towns of Serres and Amphipolis near the Strymon River and met them at Demetritzes. Branas rejected Norman’s requests for a peace treaty and attacked on November 7.
The Normans were unable to handle the aggressive Byzantine attack and were defeated after a lengthy battle; their two main commanders were captured. The remaining Norman army fled first to Thessalonica and then back home by the sea, but many of their ships were lost in storms. The remaining Normans at Thessalonica were massacred by the Alans who had joined the Byzantine army. The Battle of Demetritzes ended the Norman threat to the empire, but it was less than two decades away from almost total defeat.