 The Jin were weakened by the pressure of the rising Mongols to the north , a series of floods culminating in a Yellow River flood in 1194 that devastated Hebei and Shandong in northern China , and the droughts and swarming locusts that plagued the south near the Huai . The Song were informed of the Jurchen predicament by their ambassadors , who traveled twice a year to the Jin capital , and started provoking their northern neighbor . The hostilities were instigated by chancellor Han Tuozhou . The Song Emperor Ningzong ( r . 1194 – 1224 ) took little interest in the war effort . Under Han Tuozhou 's supervision , preparations for the war proceeded gradually and cautiously . The court venerated the irredentist hero Yue Fei and Han orchestrated the publishing of historical records that justified war with the Jin . From 1204 onwards , Song armed groups raided Jin settlements . Han Tuozhou was designated the head of national security in 1205 . The Song funded insurgents in the north that professed loyalist sympathies . These early clashes continued to escalate , partly abetted by revanchist Song officials , and war against the Jin was officially declared on June 14 , 1206 . The document that announced the war claimed the Jin lost the Mandate of Heaven , a sign that they were unfit to rule , and called for an insurrection of Han Chinese against the Jin state . 
 The Jin <a href='uninflect' title='1'><mark>were</mark></a> weakened by the pressure of the rising Mongols to the north , a series of floods culminating in a Yellow River flood in 1194 <a href='null_relcl' title='2'><mark>that</mark></a>devastated Hebei and Shandong in northern China , and the droughts and swarming locusts <a href='null_relcl' title='3'><mark>that</mark></a>plagued the south near the Huai . The Song <a href='uninflect' title='4'><mark>were</mark></a> informed of the Jurchen predicament by their ambassadors , <a href='null_relcl' title='5'><mark>who</mark></a><a href='been_done' title='6'><mark></mark></a> traveled twice a year to the Jin capital , and started provoking their northern neighbor . The hostilities <a href='uninflect' title='7'><mark>were</mark></a> instigated by chancellor Han Tuozhou . The Song Emperor Ningzong ( r . 1194 – 1224 ) took little interest in the war effort . Under Han Tuozhou <a href='null_genetive' title='8'><mark>'s</mark></a>supervision , preparations for the war proceeded gradually and cautiously . The court venerated the irredentist hero Yue Fei and Han orchestrated the publishing of historical records <a href='null_relcl' title='9'><mark>that</mark></a>justified war with the Jin . From 1204 onwards , Song armed groups raided Jin settlements . Han Tuozhou was designated the head of national security in 1205 . The Song funded insurgents in the north <a href='null_relcl' title='10'><mark>that</mark></a>professed loyalist sympathies . These early clashes continued to escalate , partly abetted by revanchist Song officials , and war against the Jin was officially declared on June 14 , 1206 . The document <a href='null_relcl' title='11'><mark>that</mark></a>announced the war claimed the Jin lost the Mandate of Heaven , a sign that they <a href='uninflect' title='12'><mark>were</mark></a> unfit to rule , and called for an insurrection of Han Chinese against the Jin state . 
The Jin was weakened by the pressure of the rising Mongols to da north , a series of floods culminating in a Yellow River flood in 1194 devastated Hebei and Shandong in northern China , and the droughts and swarming locusts plagued tdasouth near thdauai . The Song was informed of the Jurchen predicament by their ambassadors ,  done traveled twice a year to thedan capital , and started provoking their northern neighbor . The hostilities was instigated by chancellor Han Tuozhou . The Song Emperor Ningzong ( r . 1194 – 1224 ) took little interest in the war effort . Under Han Tuozhou  supervision , preparations fir the war proceeded gradually and cautiously . The court venerated the irredentist hero Yue Fei and Han orchestrated the dalishing of historical records justified war with the Jin . From 1204 onwards , Song armed groups raided Jin settlements . Han Tuozhou was designated the head of national security in 1205 . The Song funded insurgents in the north professed loyalist sympathies . These early clashes continued to escalate , partly abetted by revanchist Song officials , and war against the Jdawas officially declared on June 14 , 1206 . The dodaent announced the war claimed the Jin lost the Mandate of Heaven , a sign dat they was unfit to rule , and called for an insurrection of Han Chinese against the Jin state .