My contribution to this panel will address issues of bureaucratic management in frontier territory through the double lens of historiography and ethnography by focusing on the little studied Man shu 蠻書, or Book of the barbarians, a ninth century work by the official Fan Chuo 樊綽. The tumultuous history of Yunnan under the Tang, and the fact that “Man shu” is only one of the retrospective titles attributed to Fan Chuo’s work – alternative titles include Yunnan zhi 雲南志 (Gazetteer of Yunnan) and Yunnan shiji 雲南史記 – suggest that this work was as much an ethnographic account of frontier/unruly people as it was a bureaucratic attempt at ordering the information known at the time about a zone that was not politically integrated in the Tang empire. Specifically, I will explore two intertwined directions. First, I will probe whether this ethnographic account could or should be understood as a proxy for an actual administrative and fiscal survey of frontier territory. Second, this will help assess the importance of this text for the history of geographical knowledge, as it was produced during a period when local writings underwent important changes, from Six Dynasties accounts on local customs and oddities to Song and later local gazetteers.