Jin-Song Wars in the context of "Jingkang Incident"

The fire lance (simplified Chinese: 火枪; traditional Chinese: 火槍; pinyin: huǒqiāng; lit. 'fire spear') was a gunpowder weapon used by lighting it on fire, and is the ancestor of modern firearms. It first appeared in 10th–12th century China and was used to great effect during the Jin-Song Wars. It began as a small pyrotechnic device attached to a polearm weapon, used to gain a shock advantage at the start of a melee. As gunpowder improved, the explosive discharge was increased, and debris or pellets added, giving it some of the effects of a combination modern flamethrower and shotgun, but with a very short range (about 3 meters or 10 feet), and only one shot (although some were designed for two shots). By the late 13th century, fire lance barrels had transitioned to metal material to better withstand the explosive blast, and the lance-point was discarded in favor of relying solely on the gunpowder blast. These became the first hand cannons.

Emperor Gaozong of Song (12 June 1107 – 9 November 1187), personal name Zhao Gou, courtesy name Deji, was the tenth emperor of the Chinese Song dynasty and the first of the Southern Song dynasty, ruling between 1127 and 1162 and retaining power as retired emperor from 1162 until his death in 1187. The ninth son of Emperor Huizong and a younger half-brother of Emperor Qinzong, Zhao Gou was not present in the capital of Bianjing (the modern day Kaifeng) when it fell to the Jurchen-led Jin dynasty in 1127 during the beginning of the Jin-Song Wars. Narrowly avoiding capture by Jin forces, he escaped first to Yangzhou and then Lin'an (the modern day Hangzhou), assuming the throne and re-establishing the Song court. Despite initial setbacks, including Jin invasions and a brief deposition in 1129, Emperor Gaozong consolidated his political position and presided over the continued military conflict with Jin. Prior to 1141, military commanders including Han Shizhong and Yue Fei reconquered portions of the Central Plains while chancellors like Lü Yihao, Zhao Ding, Zhang Jun, and Qin Hui managed the civil bureaucracy.

In 1141, Gaozong collaborated with Qin to pursue a peace settlement with Jin. Although the resulting Treaty of Shaoxing ceded the Central Plains and formally established Song as a Jin tributary, it ensured two decades of uninterrupted peace, allowing the Southern Song state to achieve internal stability and open a lucrative trade with Jin. Furthermore, it served to preclude the return of Emperor Qinzong, who remained in captivity in Jin and whose release could have jeopardized Gaozong's claim to the throne. Gaozong and Qin then secured court control over the military, forcing Han Shizhong and the general Zhang Jun into retirement and executing Yue Fei on trumped-up charges. Despite his successes as emperor, Gaozong's treatment of Yue, who was remembered as a culture hero, and his surrender of over half of Song China to the enemy, marred his reputation in both traditional historiography and popular memory. Gaozong, along his father and half-brother, were blamed for the Song dynasty's decline.