This article is an attempt to confirm the chronology of the four official state documents (guoshu 國書) issued by the Tang emperor to the Kirghiz ruler during the Huichang 會昌 Era (841-846), then analyze the process by which they were drafted. The Huichang Era was a time marked by a transition from Uighur to Kirghiz rule in Mongolia, a development which the Tang Dynasty had to heed with caution, leading to the drafting and issuance of state documents, the process of which is described in part in the extant historiography. Despite the importance of this event in the study of Tang period diplomatics, the related sources have yet to be analyzed in detail. The four documents of state in question were issued to the Kirghiz in the following order: 1) “To the King of the Kirghiz” 25th -30th day of the 2nd month of Huichang 3 (843); 2) “To the Qaghan of the Kirghiz” during the 3rd month of Huichang 3 (843); 3), “To the Qaghan of Kirghiz” during the following 6th month; and 4) “To the Kirghiz” during the 2nd month of Huichang 4 (844). An analysis of the Chinese renditions of the name “Kirghiz” reveals that diplomatic letters brought by the Kirghiz envoys were not written in Chinese, but rather written either in Turk-runic presented orally, then translated into Chinese by official translators of the Imperial Secretariat (Zhongshu-sheng 中書省) before being submitted to the emperor. During the late Tang Period, imperial orders for the drafting of documents of state would be directed to either chancellors, drafters of proclamations (Zhizhigao 知制誥), Secretariat clerks (Zhongshu Sheren 中書舍人), or scholars of the Hanlin 翰林 Imperial Academy. When the chancellor was ordered to draft a document of state, he would receive an imperial directive to that effect, then make a draft based on the result of other ministers’ conference with the foreign diplomats concerned, resulting in a manuscript that would be submitted to the emperor; and in the case of the documents sent to the Kirghiz, the original manuscripts were authored by de facto Chancellor Li Deyu 李德裕 (according to his collected works Huichang Yipin Ji 會昌一品集) and rewritten with amendments proposed by Emperor Wuzong 武宗 himself, before being issued to the Kirghiz.