Kong Xun was born in 884, during the reign of Emperor Xizong of Tang, but his ancestry and home territory has been lost to history, as was his original personal name.
While serving in that office, he participated in plotting, at Zhu's order, the assassination of Emperor Zhaozong in late 904, along with Jiang Xuanhui (蔣玄暉) and Zhang Tingfan (張廷範).
Jiang Xuanhui, Zhang Tingfan, and another of Zhu's associates, the chancellor Liu Can, thus were preparing various traditional ceremonial steps for the dynastic transition, including the creation of Zhu to a princely title greater than the Prince of Liang title that he carried at that time and also the bestowment of the nine bestowments.
[8] As of 926, Kong Xun was serving as the acting prefect of Bian Prefecture, when Emperor Zhuangzong was facing multiple rebellions against him due to the resentment of the people and his own generals.
Kong decided to play both sides, so he sent emissaries to both Emperor Zhuangzong and Li Siyuan welcoming them, while secretly informing his subordinates, "Whoever gets here first will get to enter."
[1] When Emperor Zhuangzong realized this, he returned to Luoyang,[9] where he was then killed in a mutiny headed by the officer Guo Congqian (郭從謙).
Emperor Mingzong briefly put Kong Xun in charge of Bian Prefecture, and he arrested the mutineers' family members — some 3,000 households — and slaughtered them.
[10] Meanwhile, Kong developed an alliance with fellow chief of staff An Chonghui, who was a close associate of Emperor Mingzong's and who was very powerful in his administration.
Kong did not like the idea of having more chancellors from north of the Yellow River (i.e., from the region of Later Tang's predecessor state Jin, as opposed to the former Later Liang realm south of the Yellow River), and so was recommending Zheng Jue and Cui Xie, while the chancellor Ren Huan recommended Li Qi.
[10] After Emperor Zhuangzong's death, Gao Jixing the military governor of Jingnan Circuit (荊南, headquartered in modern Jingzhou, Hubei) the Prince of Nanping, who was already acting somewhat independently of the imperial government, became even more independent-acting, including attacking nearby prefectures and taking them under his control.
[11] During this time, there was a commoner at Luoyang who violated the ban against private brewing of liquors (which was a state monopoly), and Kong reacted by slaughtering his entire family.
In spring 928, he had Kong made the military governor of Zhongwu Circuit (忠武, headquartered in modern Xuchang, Henan), ejecting him from the imperial government, although Kong continued to carry the honorary chancellor title of Tong Zhongshu Menxia Pingzhangshi (同中書門下平章事) and defender of Luoyang as honorary titles.
[11] Kong was subsequently made the military governor of Henghai Circuit (橫海, headquartered in modern Cangzhou, Hebei).