Northern European - NE
Southern European - SE
Eastern Eurpoean - EE
Middle Eastern - ME

there are two types of bodyguard units for each region:

NE Bodyguard, NE Late Bodyguard
SE Bodyguard, SE Late Bodyguard... etc

Mongolian BG is Mongol Bodyguard, Greek is Greek Bodyguard. they are all in the export_descr_unit file.