 In 466, Liu Zixun waged an unsuccessful civil war against the Emperor Ming of Liu Song.The governors of Xu Province (徐州) and Yan Province (兗州, modern western Shandong), who earlier pleaded allegiance to Liu Zixun, in fear of reprisal from the Liu Song Emperor, surrendered these territories to rival Northern Wei.Northern Wei forces quickly took up defense position against the attacking forces sent by Emperor Ming.