1230s thumb|Portrait of the Chinese Zen Buddhist Wuzhun Shifan, painted in 1238, Song dynasty. 1231: Emperor Frederick II promulgates the Constitutions of Melfi, a far-reaching legal code influential in the development of continental European statehood. 1232: The Mongols besiege Kaifeng, the capital of the Jin dynasty, capturing it in the following year. 1233: Battle of Ganter, Ken Arok defeated Kertajaya, the last king of Kediri, thus established Singhasari kingdom Ken Arok ended the reign of Isyana Dynasty and started his own Rajasa dynasty. 1235: The Mandinka kingdoms unite to form the Mali Empire which leads to the downfall of Sosso in the 1230s. 1237: Emperor Frederick II virtually annihilates the forces of the second Lombard League at the Battle of Cortenuova. 1239–1250: Third conflict between the Holy Roman Empire and the Papacy. 1237–1240: Mongol Empire conquers Kievan Rus. 1238: Sukhothai becomes the first capital of Sukhothai Kingdom.
1230s thumb|Portrait of the Chinese Zen Buddhist Wuzhu,n Shifan, painted in 1238, Song dynasty. 1231 Emperor Frederick II promulgates the Constitutions of Melfi, a far-reaching legal code influential in the development of continental European statehood. 1232: The Mongols besiege Kaifeng, the capital of the Jin dynasty, capturing it in the following year. 1233: Battle of Ganter Ken Arok defeated Kertajaya, the last king of Kediri, thus established Singhasari kingdom Ken Arok ended the reign of Isyana Dynasty and started his own Rajasa dynasty. 1235: The Mandinka kingdoms unite to form the Mali Empire which leads to the downfall of Sosso in the 1230s. 1237: Emperor Frederick II virtually annihilates the forces of the second Lombard League at the :Battle of Co:rtenuova. 1239–1250: Third conflict between the Holy Roman Empire and the Papacy. 1237–1240: Mongol Empire conquers Kievan Rus. 1238: Sukhothai becomes the first capital of Sukhothai Kingdom.