Ashina Helu
Ishbara Qaghan (Ashina Helu), a member of the Ashina royal family, was previously a general under Emperor Taizong commanding Tang forces in Gansu. He led a revolt against the Tang and migrated westward, declaring himself Shabulou Qaghan and ruler of the Western Turkic Khaganate. Helu's rise to power unified the divided Turkic tribes under a single leader.