GADM is a database of the location of the world's administrative areas (boundaries).
Administrative areas in this database are countries and lower level subdivisions. GADM describes where these administrative areas are (the "spatial features"), and for each area it provides some attributes, foremost being the name and in some cases variant names. The data are in ESRI shapefile and geodatabase format.
From http://www.gadm.org/ one can download country level files (recommended) or files covering the entire world.
The development of GADM was partly supported by the Gordon and Betty Moore foundation for the BioGeoMancer project. The work was done at the University of California, Berkeley, Museum of Vertebrate Zoology, and the International Rice Research Institute
Notable fields include: NAME (in native language and in English), ALTERNATE NAMES (in native language and in English), TYPE (in native language and in English), VALID FROM and VALID TO dates, and REMARKS.