Editing 756 (section)

==== Byzantine Empire ====
* [[Byzantine–Bulgarian wars#Constantine V's wars|Byzantine–Bulgarian War]]: Emperor [[Constantine V]] builds a series of [[fortification]]s along the Byzantine frontier on the [[Danube]], and starts settling Christian [[Armenians]] and [[Syria]]ns in the [[Thracesian Theme]]. In response, [[Kormisosh]], ruler (''[[khagan]]'') of the [[First Bulgarian Empire|Bulgarian Empire]], demands the payment of [[tribute]]. Constantine refuses, and the [[Bulgars]] raid into Thrace, reaching the [[Anastasian Wall]] stretching between the [[Black Sea]] and the [[Sea of Marmara]] (near the [[Rural–urban fringe|outskirt]]s of [[Constantinople]]). 
* [[Battle of Marcellae (756)|Battle of Marcellae]]: Constantine V sends a Byzantine expeditionary force (500 ships and 6,000 [[cavalry]]) to [[Thrace]], and defeats the Bulgars around the [[Danube Delta]] and near the fortress city of [[Markeli]] (modern [[Bulgaria]]). Kormisosh is forced to accept a [[peace treaty]], and confirms the existing frontier.<ref>Runciman S., ''A History of the First Bulgarian Empire'', London G.Bell & Sons, 1930, pp. 37, 289.</ref> Due to the constant political crisis, the Bulgarian Empire is on the verge of destruction. Kormisosh is deposed during a palace [[coup d'état|coup]] and succeeded by [[Vinekh]], a member of the [[Vokil]] clan.