Eastern Europe- Albania, Bosnia/ Herzegovnia, Bulgaria, Croatia, Czech Republic, Hungary, Macedonia, Montenegro, Poland, Romania, Serbia, Slovakia, Slovenia.
Western Slavs (pink)- Belarus (White Russia), Russia, Ukraine.
Eastern Slavs (purple)- Czech Republic, Poland, Slovakia.
Southern Slavs (blue-purple)- Bulgaria, Croatia, Macedonia, Serbia, Slovenia.
Balkans (blue and blue spotted)- Albania, Bosnia/ Herzegovnia, Bulgaria, Croatia, Greece, Macedonia, Montenegro, Serbia, Slovenia.
Map provided by the Univeristy of Texas (Click on the map for a link).
Sources vary as to what countries are Balkan, Eastern European, etc. I grouped countries according to the lists in:
The World Book Encyclopedia
World Book Inc.