Khazar invasion of Transcaucasia

Third Perso-Turkic War
Part of Byzantine–Sassanid War of 602–628
Date 627–629 Location Transcaucasia Result Turco-Byzantine victory
Belligerents
Sassanid Empire (Persia), Caucasian Iberia	Western Turkic Khaganate, Byzantine Empire
Commanders and leaders
Khosrow II, Shahrbaraz, Stephen I of Iberia	Heraclius, Böri Shad, Tong Yabghu Qaghan

The Third Perso-Turkic War was the third and final conflict between the Sassanian Empire and the Western Turkic Khaganate. Unlike the previous two wars, it was not fought in Central Asia, but in Transcaucasia. Hostilities were initiated in 627 AD by Khagan Tong Yabghu of the Western Göktürks and Emperor Heraclius of the Eastern Roman Empire. Opposing them were the Sassanid Persians, allied with the Pannonian Avars. The war was fought against the background of the last Byzantine-Sassanid War and served as a prelude to the dramatic events that changed the balance of powers in the Middle East for centuries to come (Battle of Nineveh, Islamic conquest of Persia).

Following the First Siege of Constantinople by the Avars and Persians, the beleaguered Byzantine Emperor Heraclius found himself politically isolated. He could not rely on the Christian Armenian potentates of Transcaucasia, since they were branded as heretics by the Orthodox Church, and even the king of Iberia preferred to befriend the religiously tolerant Persians. Against this dismal background, he found a natural ally in Tong Yabghu. Earlier in 568, the Turks under Istämi had turned to Byzantium when their relations with Persia soured over commerce issues. Istämi sent an embassy led by the Sogdian diplomat Maniah directly to Constantinople, which arrived in 568 and offered not only silk as a gift to Justin II, but also proposed an alliance against Sassanid Persia. Justin II agreed and sent an embassy to the Turkic Khaganate, ensuring the direct Chinese silk trade desired by the Sogdians.

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