Guzang (439) — the same event in History of the Northern Dynasties, Book of Wei and Zizhi Tongjian

History of the Northern Dynasties: After besieging Guzang, Juqu Mujian of the Northern Liang surrendered at the military gate with five thousand…

What each source says

History of the Northern Dynasties (Beishi), Annals · AD 439 · 姑臧

After besieging Guzang, Juqu Mujian of the Northern Liang surrendered at the military gate with five thousand civil and military officials, and over two hundred thousand households came under control.

丙戌,牧犍與左右文武五千人面縛軍門
Location: 北史 卷2 太延5年

Book of Wei (Weishu), Imperial Annals · AD 439 · 姑臧

He reached Guzang, the capital of Northern Liang, and besieged it.

丙申,車駕至姑臧,牧犍兄子祖踰城來降,乃分軍圍之。
Location: 魏書卷4上·太延五年

Book of Wei (Weishu), Imperial Annals · AD 439

Juqu Mujian surrendered with five thousand men, bound in the posture of submission (mianbo), and the over 200,000 registered inhabitants of the city were brought under control (the fall of Northern Liang).

是日,牧犍與左右文武五千人面縛軍門,帝解其縛,待以藩臣之禮。
Location: 魏書卷4上·太延五年

Zizhi Tongjian (Comprehensive Mirror) · AD 439 · 姑臧

Northern Wei besieges Guzang; Juqu Muqian surrenders bound, and Northern Liang falls (September).

姑臧城潰,牧犍帥其文武五千人面縛請降
Location: 卷123

Place: 姑臧

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