CHGIS is a repository of historical and current spatial data about China. Data is available for download for free for academic uses. Registration is required.
“Having downloaded the CHGIS datasets, the user can search the database for administrative units and capitals for any given time in Chinese history, can create customized digital maps for particular times and places, or can join their own datasets for spatial analysis, thematic mapping, or other specialized statistical modeling according to their own interests. Also included in the datasets are layers for historical coastlines, major rivers, and generalized elevations.”