[Why] In early Southern Song, the Jin army crossed the Yangtze defense line continuously and looted, half of the realm in critical danger. The state urgently needed a strictly disciplined, fiercely combat-capable national defense military iron force to stabilize the defense line. [What] Yue Fei recruited refugees to build the strictly disciplined Yue Family Army and at Battle of Yancheng with infantry crushed the Jin's flagship cavalry. He continually recovered lost lands, vowing to drive straight to Huanglongfu, but was forcibly recalled by twelve gold tablets and killed. [Who] Yue Fei was an outstanding national hero of serving the country with pure loyalty, lofty martial virtue, called the god of war. Emperor Gaozong and Chancellor Qin Hui out of partial-state private interest and fear of military power jointly killed the loyal good as the culprits. [How] The Yue Family Army's resistance defense definitively shattered the myth of the Jin invincible steppe cavalry and successfully secured Jiangnan society's development safety. Yue Fei also became the Huaxia nation's supreme symbol of loyal-courage moral integrity and state moral integrity.
Why
The historic event of Yue Fei's Campaigns represents a key developmental peak of the Huaxia dynastic system. The ultimate symbol of national defense and military dedication. By establishing this moral or administrative benchmark, it continues to shape the structural and philosophical fabric of ancient Chinese statecraft.