 The wars engendered an era of technological , cultural , and demographic changes in China . Battles between the Song and Jin brought about the introduction of various gunpowder weapons . The siege of De 'an in 1132 was the first recorded appearance of the fire lance , an early ancestor of firearms . There were also reports of battles fought with primitive gunpowder bombs like the incendiary huopao or the exploding <unk> , incendiary arrows , and other related weapons . In northern China , the Jurchen tribes were the ruling minority of an empire that was predominantly inhabited by former subjects of the Northern Song . Jurchen migrants settled in the conquered territories and assimilated with the local culture . The Jin government instituted a centralized imperial bureaucracy modeled on previous Chinese dynasties , basing their legitimacy on Confucian philosophy . Song refugees from the north <unk> in southern China . The north was the cultural center of China , and its conquest by the Jin diminished the international stature of the Song dynasty . The Southern Song , however , quickly returned to economic prosperity , and trade with the Jin was lucrative despite decades of warfare . The capital of the Southern Song , Hangzhou , expanded into a major city for commerce . 
