First Siege of Constantinople

Avar-Slavic Siege of Constantinople
Part of Byzantine–Sasanian War of 602–628 and the Avar–Byzantine Wars
Depiction of the siege from the Chronicle of Constantine Manasses
Date June–July 626 Location Constantinople, Byzantine Empire Result Byzantine victory
Belligerents
Byzantine Empire	Avar Khaganate Sassanid Empire Sclaveni
Commanders and leaders
Patriarch Sergius Magister Bonus	Unnamed Avar khagan Shahrbaraz Kardarigan
Strength
12,000 men	80,000 Avars and Slavs, Persian allies

The Siege of Constantinople in 626 by the Sassanid Persians and Avars, aided by large numbers of allied Slavs, ended in a strategic victory for the Byzantines. The failure of the siege saved the Empire from collapse, and, combined with other victories achieved by Emperor Heraclius (r. 610–641) the previous year and in 627, enabled Byzantium to regain her territories and end the destructive Roman-Persian Wars by enforcing a treaty with borders status quo c. 590.

In 602, Phocas overthrew Maurice (r. 582–602), the incumbent Byzantine emperor, and established a reign of terror and incompetence, leading the Empire into anarchy. Laws were passed condemning Jews whilst religious and administrative mishandling left the Empire in a sorry state when the Sassanid king Khosrau II (r. 590–628) attacked, using the coup as a pretext for war. Initially, the war went well for the Persians, until only Anatolia remained in Roman hands. Later, Phocas was overthrown by the son of the then Exarch of Carthage, Heraclius. A general of astounding energy yet limited experience, Heraclius immediately began undoing much of Phocas's damaging work that he had procured whilst Emperor. Yet, despite his offensives into Mesopotamia (modern-day Iraq) Heraclius was unable to stop his Persian enemies from laying siege to his capital where from Chalcedon they were able to launch their attack. From 14–15 May 626, riots in Constantinople against John Seismos occurred because he wanted to cancel the bread rations of the scholae or imperial guards and raise the cost of bread from 3 to 8 follis. He did this to conserve government resources, but he was removed. However, there were further disturbances in the city.

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