Juqu Mengxun.

About Juqu Mengxun

Juqu Mengxun, also known by his posthumous name as the Prince Wuxuan of Northern Liang (北涼武宣王), was the second prince of the Lushuihu-led Chinese Northern Liang dynasty, and the first from the Juqu clan. His cousin Juqu Nancheng (沮渠男成) and he initially supported Duan Ye as prince of Northern Liang in 397 after rebelling against the Later Liang dynasty, but in 401, Juqu Mengxun tricked Duan Ye into wrongly executing Juqu Nancheng, and then used that as an excuse to attack and kill Duan Ye, taking over the throne himself. While he maintained his own state, he also nominally served as a vassal of the Later Qin, Eastern Jin, and Northern Wei dynasties. He was considered a capable ruler when he was young, but in his old age was considered cruel and arbitrary.