Remnants of the Song imperial family retreated to southern China and, after brief stays in several temporary capitals, eventually relocated to Lin'an (modern Hangzhou).

The Jurchens tried to conquer southern China in the 1130s but were bogged down by a pro-Song insurgency in the north and a counteroffensive by Song generals, including Yue Fei and Han Shizhong.

[12] The Song delayed their entry into the war because it diverted resources to fighting the Western Xia in the northwest and suppressing a large popular rebellion led by Fang La in the south.

[13] When a Song army under Tong Guan's command finally attacked Yanjing in May 1122, the smaller forces of the weakened Liao repelled the invaders with ease.

Even though the Song agreed to execute him in late 1123, this incident put tension between the two states, because the 1123 treaty had explicitly forbidden both sides from harboring defectors.

[30] Opponents of the treaty like Li Gang (李剛; 1083–1140) rallied around the proposal of remaining in defensive positions until reinforcements arrived and Jurchen supplies ran out.

[37] Wanyan Zonghan, who had withdrawn from Taiyuan after the Kaifeng agreement and left a small force in charge of the siege, came back with his western army.

Even as fighting raged on, Qinzong continued to sue for peace, but Jin demands for territory were enormous: they wanted all provinces north of the Yellow River.

[58] The Jin hoped a proxy state would be capable of administering northern China and collecting the annual indemnity without requiring Jurchen interventions to quell anti-Jin uprisings.

[59] The puppet government did not deter the resistance in northern China, but the insurgents were motivated by their anger towards the Jurchens' looting rather than by a sense of loyalty towards the inept Song court.

[62] The future Emperor Gaozong managed to evade the Jurchen troops tailing him by moving from one province to the next, traveling across Hebei, Henan, and Shandong.

[64] The court moved to Yingtianfu because of its historical importance to Emperor Taizu of Song, the founder of the dynasty, who had previously served in that city as a military governor.

On the western front, an army invaded Jiangxi, the area where the Song dowager empress resided, and captured Hongzhou (洪州, present-day Nanchang).

[76] The Jin seized Hangzhou (January 22, 1130) and then Shaoxing further south (February 4), but general Zhang Jun's (1086–1154) battle with Wuzhu near Ningbo gave Gaozong time to escape.

[77] After they plundered the undefended cities of Hangzhou and Suzhou, they finally started to face resistance from Song armies led by Yue Fei and Han Shizhong.

[82] The natural barriers that surrounded Lin'an, including lakes and rice paddies, made it more difficult for the Jurchen cavalry to breach its fortifications.

[88] The Jin requirement that the border between the two states be moved south from the Huai River to the Yangtze was too large of a hurdle for the two sides to reach an agreement.

[90] The Qi government instituted military conscription, made an attempt at reforming the bureaucracy, and enacted laws that enforced the collection of high taxes.

[89] The armies of Qi and Jin won a series of victories in the Huai valley, but were repelled by Han Shizhong near Yangzhou and by Yue Fei at Luzhou (廬州, modern Hefei).

Gaozong first agreed, but he abandoned the counteroffensive when an officer named Li Qiong (酈瓊) killed his superior official and defected to the Jin with 30,000 soldiers.

[100] The government weakened the military by rewarding Yue Fei, Han Shizhong, and Zhang Jun (1086–1154) with titles that relieved them of their command over the Song armies.

[122] Traditional Chinese accounts consider this the turning point of the war, characterizing it as a military upset that secured southern China from the northern invaders.

[131] The court venerated the irredentist hero Yue Fei and Han orchestrated the publishing of historical records that justified war with the Jin.

[132] Song armies led by general Bi Zaiyu (畢再遇; d. 1217) captured the barely defended border city of Sizhou 泗州 (on the north bank of the Huai River across from modern Xuyi County) but suffered large losses against the Jurchens in Hebei.

[135] The Jin initiated an offensive against Song prefectures in the central front of the war, capturing Zaoyang and Guanghua (光化; on the Han River near modern Laohekou).

[137] The failure of Han Tuozhou's aggressive policies against the Jurchens by this time round had depopularised him amongst the common people which situation was exploited by the Empress Yang and Shi Miyuan, his most powerful political rivals to garner support amongst other courtiers which led to his demise.

[152] In the east, the Jin made little headway in the Huai River valley, but in the west they captured Xihezhou and Dasan Pass (大散關; modern Shaanxi) in late 1217.

[112] The Jin government initially promoted an independent Jurchen culture alongside their adoption of the centralized Chinese imperial bureaucracy, but the empire was gradually sinicized over time.

[172] Once retaking northern China became less plausible and Lin'an grew into a significant trading city, the government buildings were extended and renovated to better befit its status as an imperial capital.

Government revenues earned from taxing foreign trade nearly doubled between the closing of the Northern Song era in 1127 and the final years of Gaozong's reign in the early 1160s.