Western Qin
Qifu Mumo first had to face a major attack that Juqu Mengxun launched against Western Qin in light of his father's death. As his father had instructed before death, Qifu Mumo sent Juqu Chengdu (沮渠成都), a Northern Liang general whom Qifu Chipan captured in 422, whom Juqu Mengxun respected, back to Northern Liang, and the states entered into a peace agreement. However, just several months later the peace appeared to be over, for Juqu Mengxun resumed his attacks on Western Qin. In spring 429, Juqu Mengxun captured Xiping.