 The joint attack against the Liao had been planned for 1121 , but it was rescheduled for 1122 . In February 23 of that year , the Jin captured the Liao Central Capital as promised . 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 in the south . 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 . Another attack failed in the fall . Both times , Tong was forced to retreat back to Kaifeng . After the first attack , Aguda changed the terms of the agreement and only promised Yanjing and six other prefectures to the Song . In early 1123 it was Jurchen forces that easily took the Liao Southern Capital . They sacked it and enslaved its population . 
 The joint attack against the Liao <a href='been_done' title='1'><mark>had</mark></a> been planned for 1121 , but it was rescheduled for 1122 . In February 23 of that year , the Jin captured the Liao Central Capital as promised . 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 in the south . When a Song army under Tong Guan <a href='null_genetive' title='2'><mark>'s</mark></a>command finally attacked Yanjing in May 1122 , the smaller forces of the weakened Liao repelled the invaders with ease . Another attack failed in the fall . Both times , Tong was forced to retreat back to Kaifeng . After the first attack , Aguda changed the terms of the agreement and only promised Yanjing and six other prefectures to the Song . In early 1123 it was Jurchen forces <a href='null_relcl' title='3'><mark>that</mark></a>easily took the Liao Southern Capital . They sacked it and enslaved its population . 
Da joint attack against the Liao done been planned for 1121 , but it was rescheduled for 1122 . In February 23 of that year , tdaJin captured thdaiao Central Capital as promised . The Song delayed their entry into the war cuz it diverted resources to fighting thedastern Xia in the dathwest and suppressing a bigass popular rebellion in the south . When a Song army under Tong Guan  command finally attacked Yanjing in May 1122 , the smaller forces of the weakened Liao repelled the invaders with ease . Another attack failed in the fall . Both times , Tong was forced to retreat bck to Kaifeng . After the fdat attack , Aguda changed the terms of the agdament and only promised Yanjing and six other prefectures to the Sonda In early 1123 it was Jurchen forces easily took the Liaodauthern Capital . They sacked it and enslaved its population .