兖州 / Yanzhou (Late Han)
兖州 / Yanzhou (Late Han) enters the wiki through Hanji 987 as 曹操’s contested root base. 荀彧 argues that Cao Cao should not leave the province to pursue 徐州 while 吕布, 张邈, and their allies still threaten the rear. In the episode’s analogy, Yanzhou is to Cao Cao what 关中 is to Liu Bang and 河内 is to Liu Xiu: the base that makes both attack and defense possible.
The source makes Yanzhou a material as well as symbolic base. Its wheat harvest, people-support, city defense, and road security decide whether Cao Cao can sustain any later offensive. If he abandons it too soon, he may keep only a few strongholds while losing the province that made his army and authority operational.
Hanji 989 gives the closing turn of the same branch. Cao Cao surrounds 雍丘, Zhang Miao tries to flee toward 袁术, and 刘翊 kills him before that exit can strengthen an enemy camp. The episode then reports Cao Cao’s appointment as Yanzhou governor, making the province a formal as well as battlefield base.
The later Zang Hong branch keeps Yanzhou’s aftershocks visible. Hanji 996 remembers that Zhang Miao had welcomed Lü Bu into Yanzhou against Cao Cao, which helps explain why Cao Cao will not spare 张超 at Yongqiu. Hanji 1000 later makes the Yanzhou gentry channel part of 陈宫’s protected position inside Lü Bu’s camp.