Wu Xi's Defection to the Jin

Timeline

1. 1207Chengdu · SichuanWu Xi seized total military and civil authority in Sichuan under the pretext of the northern expedition, ousting rivals and building a private faction. As Song forces faltered, Wu Xi secretly corresponded with the Jin court, his rebellious intentions increasingly obvious, and unease spread among local officials and gentry.
2. 1207Sichuan · SichuanWu Xi sent envoys to the Jin, offering to submit Sichuan's four prefectures. Emperor Zhangzong of Jin accepted his defection, whereupon Wu Xi proclaimed his rebellion against Song in Chengdu, changed his era name, appointed officials, and carved out a separatist regime in Ba-Shu, plunging the Song court's western defenses into an unprecedented crisis.
3. 1207Jin Zhongdu · North ChinaThe Jin court formally invested Wu Xi as King of Shu, bestowing a gold seal and edict, making him a vassal ruler of the Jin. The Jin used this to divide Song forces and tie down the western front, while the Song court urgently reorganized Sichuan's defenses and planned a suppression campaign.