In 1206, the Southern Song Dynasty's powerful minister Han Yanxuan provoked a war against the Jin Dynasty. However, due to the inadequate preparation of the Southern Song Dynasty, the Song army soon fell into passivity, and even suffered a rout on the whole front. The Jin Dynasty also launched a counterattack, occupying Zhenzhou and Yangzhou successively, and even the Dasanguan, the gateway to Sichuan and Shu, was occupied by the Jin army. At this time, the Jin Dynasty had already grasped the initiative in the war, but they did not continue to fight, and then destroyed the Southern Song Dynasty, but negotiated peace with it. What's going on here?
1. The emperor is the main peace
At that time, the emperor of the Jin Dynasty was Jin Zhangzong Wanyan Jing, he learned Han culture since he was a child, "belongs to the literature for learning, advocating elegance", is the emperor of the Jin Dynasty, the most deeply influenced by the sinicization, and the feudalization of the Jurchen was also achieved during his reign. However, Jin Zhangzong was very different from Wanyan Liang, the king of Hailing, and his policy towards the Song was heavily influenced by his grandfather, Jin Shizong. In that year, after the failure of King Hailing's southern expedition to the south of Yan Liang, Song Xiaozong, who was bent on restoring his hometown in the Central Plains, launched the "Longxing Northern Expedition".
However, the rout of the Battle of Fuli brought Song Xiaozong's Northern Expedition to an abrupt end. At this time, Jin Shizong did not plan to continue to go south, but promoted peace with force and reached the "Longxing Peace Agreement" with the Southern Song Dynasty. As Sejong's "good holy grandson", Wan Yanjing grew up under the influence of his grandfather, so after becoming emperor, Kim Jangjong continued his grandfather's policy of "peace and harmony from the inside". In 1205, the Southern Song Dynasty continued to provoke border provocations, but Jin Zhangzong believed that "the north and the south have been reconciled for more than 40 years, and the people do not know the soldiers and cannot bear to strike first".
Second, the profit is huge
At the same time, the rulers of the Jin dynasty believed that it would be beneficial for the Jin dynasty to maintain friendly relations with the Southern Song Dynasty. First, according to the provisions of the "Longxing Peace Conference", the Southern Song Dynasty had to pay a large amount of annual coins to the Jin Dynasty every year, which amounted to 200,000 taels of silver and 200,000 taels of silk. These revenues could subsidize the finances of the Jin Dynasty, and once a war broke out with the Southern Song Dynasty, this revenue would naturally be gone. Second, trade can also bring considerable fiscal revenue. According to the provisions of the Song-Jin Peace Conference, the two sides set up bars in the border areas to conduct trade.
According to historical records, the Jin Dynasty in Sizhou's Yongchang, "Dadingjian, the year was 53,467 guan, and in the first year of Cheng'an, it was increased to 107,893 guan and 653 wen." Located in Qinzhou, the income of the Xizi City Field, the income of the Rongchang trade is also very considerable, in the early years of Dading, only 33,656 guan, to the first year of Cheng'an has increased to 122,099 guan. It can be seen that maintaining peace with the Southern Song Dynasty can bring huge "economic benefits" to the Jin Dynasty.
3. Internal and external troubles
In the face of the Southern Song Dynasty's "Kaixi Northern Expedition", although Jin Zhangzong repelled the Song army and invaded the territory of the Southern Song Dynasty, he did not have the idea of destroying the Southern Song Dynasty. Because of the situation at home and abroad at this time, he has no intention of going south. The first is internal worries. At that time, various natural disasters continued to break out in the Jin Dynasty, especially the Yellow River burst its banks three times, and "ten people died of starvation". On the one hand, it was necessary to provide relief to the victims, and on the other hand, it was necessary to build water conservancy, which greatly consumed the financial revenue of the Jin Dynasty.
After the flood and drought disaster, peasant uprisings continued to break out in various places, which also affected the national strength of the Jin Dynasty. At this time, there were also many contradictions within the court, and Jin Zhangzong's favor Li Shi'er colluded with Xu Zhiguo to specialize in court politics, which intensified the contradictions between the court and the country. The second is external troubles. At this time, on the northern steppe, Mongolia had risen, constantly invading the borders of the Jin Dynasty, and also containing the power of the Jin Dynasty. Under these circumstances, Jin Zhangzong naturally did not want to go to war with the Southern Song Dynasty again. So, do you think Jin Zhangzong's policy toward the Song Dynasty is reasonable?
References: 1. "Golden History"; 2. "History of the Song Dynasty"