"Here's one hint: Most languages evolved from Sanskrit. It's amazing how much is from Sanskrit, and dictionaries do not state this. They'll say Old French, or Latin, or something. But my primitive knowledge of Sanskrit informs me otherwise, plus there is much documentation of this that I have read."
It would be better to say that Sanskrit and the Western Indo-European languages are both Indo-European, and devolved from the same parent tongue or tongues. Yes, Sanskrit and Latin have similarities. So do Latin, Greek and Gaelic. Part is no doubt influence of neighbors (the Romans sucked up Greek culture like Californians suck up Italian leather goods), but with the Hindus and the Gaels, who obviously didn't have any meaningful contact until recent times, that their languages are related is evidence of the common parentage.
Nor is it really difficult to see how that parentage came about. North of India and east of Europe is a great sweeping plain, "The Steppe". Now, the Steppe is a crappy place to live, but absent Gengis Khan and his horse armies, it's a real easy place to cross, much easier than climbing mountains or wading through primeval forests. And if you look, that plain that contains the Steppe sweeps from Flanders all the way to the Tarim Basin of China.
It isn't really surprising that the languages of the people on the OTHER SIDE of the mountains from the step all show common roots (Tocharian in the Chinese Basin), Sanskrit and Hindi in India, Hittite in old Anatolia, Iranian (Aryan), and of course all of the Western languages at the European end of that plain.
If one follows the logic, an original linguistic family lived there and migrated and spread out across it, but then their own population pressure (the Steppe is great superhighway in an age without roads, but it's not a very pleasant place to live) and eventually the pressure of people behind them...the Altaic peoples (Mongols and the like) who live on the Steppe NOW ... drove the Indo-Europeans across the respective mountains rimming the step and sundered them one from the other. 'Twas the 19th Century linguists of the European Empires who noticed the striking similarities between Sanskrit and Latin and Greek.
But we should not go too far and suggest that Western languages CAME FROM Sanskrit. They are, rather, cousins of a common parent, long sundered by vast distances and interposing peoples.
Excellent overview and it 'jives' with my thinking.
The deep steppes we impassible and uninhabitable until two things occurred, the domestication of the horse and the invention of the wheel. The domestication of the horse prompted the invention of the first pair of pants too.
With all due respect, I hold that Sanskrit is the ancient language from which the Indo-European languages derived. I am a student of the Vedas (can't read Devanagari, but do have a very simple appreciation of a lot of Sanskrit terms as long as they are written in my alphabet!). The Vedas themselves describe their origin and the time frame is very, very ancient. The original British Indologists had a conscious motivation to obfuscate the great antiquity of India's history and the Vedas. For instance, they posited the idea that the Greeks influenced India, when it was in truth the other way around.
I've read quotes (wish I had them handy) of one British Indologist admitting their knowingly lying in this regard. Also, the so-called Aryan invasion theory is also proving to be false. It's a fascinating topic, which unfortunately I don't have time for. Wish I did.
Maybe they devolved, but not much. BTW, the winning word in the national spelling bee was Ursprache, which we are now allowed to use as if it were an English word rather than German.