Western Turkic Khaganate

The Western Turkic Khaganate was formed as a result of the internecine wars in the beginning of the 7th century (600 – 603 AD) after the Göktürk Khaganate (founded in the 6th century in Northern Mongolia by the Ashina clan) had splintered into two polities – Eastern and Western. The Western Turks (also known as the Onoq, or "ten arrows") sought friendly relations with the Byzantine Empire in order to expand their territory at the expense of their mutual enemy, the Sassanid Empire. In 619 the Western Turks invaded Bactria but were repulsed in the course of the Second Perso-Turkic War. During the Third Perso-Turkic War Khagan Tung Yabghu and his nephew Buri-sad joined their forces with Emperor Heraclius and successfully invaded Transcaucasia.
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