By 638, it was said that Ashina Tong'e had lost the hearts of the people, and the northern half of the khanate supported an Eastern Turkic prince, Ashina Yugu as Yipiduolu Khan. There were major battles between Ashina Tong'e and Ashina Yugu, but neither side was able to prevail, and therefore divided the khanate in two, with the Ili River serving as their boundary. The division continued after Ashina Tong'e died in 639 and was succeeded by his nephew Ashina Bobu (as Shaboluoyehu Khan).