The Case of Yan Wu, Military Governor of Jiannan, Memorializing the Execution of the Rebel General Han Cheng of Zizhou in the First Year of Yongtai

In 765 AD, during the reign of Emperor Daizong of Tang, Yan Wu, the powerful military governor of Jiannan Circuit, submitted an urgent memorial to the imperial court accusing Han Cheng, a general stationed in Zizhou, of conspiring to mutiny and defect to rival forces. Yan Wu asserted that immediate execution was imperative to forestall a broader regional insurrection. The imperial court, relying heavily on Yan Wu's judgment and authority in the aftermath of the An-Shi Rebellion, sanctioned the summary beheading. Han Cheng was promptly executed. This case unfolded against the backdrop of escalating military governor autonomy, occurring shortly before Yan Wu's own death later that same year.

Han Cheng was summarily found guilty of treason and executed by beheading following imperial endorsement of Yan Wu's memorial.

The central controversy lies in the veracity of the rebellion charges. Due to sparse and fragmented historical documentation, it remains deeply ambiguous whether Han Cheng genuinely orchestrated a mutiny or whether he fell victim to Yan Wu's political purge aimed at consolidating unchallenged control over the strategic Jiannan region.

The execution starkly illustrated the enormous discretionary power held by regional military governors in the post-rebellion Tang Dynasty. It demonstrated how a governor could leverage imperial authority to eliminate perceived threats with minimal central oversight, thereby reinforcing the decentralization of military and judicial power that would eventually contribute to the dynasty's fragmentation.