It turns out that most of the major language families are related into one superfamily, referred to as Indo-European. Discussion about actual Proto-Indo-European civilization has been set back by its association with Hitler's Aryan doctrine, but they probably lived some place about the CaspianSea
? around 2000 B.C. Huge dictionaries have been compiled of inferred PIE words.
The various subgroups of Indo-European had diverged and spread by about 1500 B.C., and include
CelticLanguages?
GermanicLanguages
ItalicLanguages?
IllyrianLanguages?
GreekLanguage?
SlavicLanguages
AnatolianLanguages?
IndoIranianLanguages, e.g. SanskritLanguage?