Some linguists say PIE was first spoken in Anatolia but most agree it emerged from the Russian steppes. However there are a huge number of Indian nationalists who say that all Indo-European languages began in India (as well as pretty much everything else in the history of mankind). There is one argument made which concerns words in Slavic and Indo-Aryan languages relating to farming and agriculture and concludes that an Aryan migration out of India into Eastern Europe resulted in the Slavic language group. One essay by Joseph Skulj, Jagdish C. Sharda, Snejina Sonina and Ratnakar Narale makes the following claim.
“We estimate that the split between Indo-Aryans and the ancestors of slavs occurred after the
domestication of the sheep and cattle, about 10,000 years ago but before cereal farming became a common industry amongst the ancestors of Slavs in Europe and Indo-Aryans on the Indian sub-continent.”
There are several problems with such theories. One is that there is less linguistic diversity in Northern India than Central Eastern Europe, making it less likely as a PIE homeland. Further evidence against the “out of India” theory is found in dialectical variation and the enormous Dravidian substrate influence on Indian languages.
The notions of Slavic/Indo-Aryan affinity also don’t account for the fact that of all living Indo-European languages, the one which most closely resembles PIE is neither Slavic nor Indo-Aryan, it is Lithuanian which is Baltic. The only other languages which comparably resemble Proto-Indo-European in terms of phonology and nominal morphology are classical ones such as Ancient Greek and Sanskrit. Baltic and Slavic languages share a common root language called Proto-Balto-Slavic, but Slavic languages are are less like PIE than Baltic ones. This is why Lithuanian is so important for people that study PIE.
Aryan Lithuanian Word Comparisons
Click here to read a detailed explanation of why accentuation patterns, consonant patterns and phonological systems in Lithuanian are so helpful for historical linguists. The following is merely a list of modern Lithuanian words compared to more ancient Indo-European cognates which the reader may find interesting. Decide for yourself if you think the “Aryan Lithuanian” theory (that’s not really a thing) is more convincing that the Slavic-Indo “out-of-India” theory.
Lith:sūnus – “son”
Sanskrit: sūnú – “son”
PIE: *suHnú – “son”
Lith: nepotis – “grandson”
Latin: nepōtis – “grandson/ nephew”
PIE: *nepot- “nephew, grandson”
Lith: výras “man”
Latin: vir “man”
Sanskrit: vīrá- “man, hero”
PIE: *wiH-ro- “man”
Lith: nosis “nose”
Latin: nāris “nose”
Old Norse: nǫs “nose”
Lith: ašva “mare
Lith: urgzti “to growl”
Ancient Greek: árktos “bear”
Lithuania was the last country in Europe to convert to Christianity. Their pagan religion was, like their language, in many ways more similar to the ancient PIE religion than other pagan religions were. You can learn a bit more about this in the following video.