Bei Prefecture

Beizhou or Bei Prefecture was a "zhou" (prefecture) in imperial China seated in modern Qinghe County in Hebei, China. It existed (intermittently) from 578 to 1048, when its name changed to En Prefecture after Wang Ze's rebellion in the prefecture.
Geography.
The administrative region of Bei Prefecture in the Tang dynasty is in the border area of southeastern Hebei and western Shandong. It probably includes parts of modern: 