Just posted this on the Samaritan Thread and it is pertainent here:
One can think of it this way, as employer & employee. If you are the employer, and the company goes bust, you are in some serious trouble. If only the employee, it is easier to move on. Ruling classes tended to be less permanent an certainly not remain in language. But some did, most notably the Indo European varieties. Tons of ethnic languages are now completely lost, where as about 10K BC there were an estimated thousand languages, and hundred or so language groups. Even Etruscan, which at least one Emperor's wife was of that group, is very slightly known for the many hundreds of years relationship with Rome. All the other Italian subgroups left without trace beyond geographical names, pretty much.
That is what exists on the island of New Guinea right now, though many are close to disappearing. Depending on how you count they have over a thousand languages, certainly hundreds of branches. Europe currently has 3 branches of native peoples, Urgaic, Basque and IndoEuropean remaining, with almost all being the latter. With the advent of horses, empires can quickly be forged and broken in a few years. Most empires did not stress the average person learning the conqueror's language, and to use the royal variety might get your head chopped off.
Rome was an exception. Even Romania, only Latin dominated for a few short years, was imposed on language that remains to this day. They must of had a plan, and it seemed to involve sheephearders and their trading fairs (in Greece and elsewhere in the Balkans, they are still known as the Vlachs).
http://www.culturalsurvival.org/publ...orn-assimilate
There is a story behind all of this, one that will never be well known, it is sad to say.
"Move on" meaning to get on with the new order of things, not normally relocated although that happened often enough too. The ruling class often had to move on in their native district, if any, or had it diminished. The Urgaic tribes, which the capital city Gelonus previously mentioned apparently was
http://en.wikipedia.org/wiki/Gelonus , were being absorbed still in recent centuries, native areas stubbornly refusing to give up remaining customs. Some areas of Russia, some 7 million or so worth, still speak the language, all to the far north and none to the Ukarainian areas where only dim remnants remain. (Hungary, Estonia, Finland, too.)
Perhaps most famous of the native local groups was in initial ancient Mesopotamia, where one wave of invaders, usually from the north, came one after another. After about 80 years, soft and fat, the pickings were ready for another crop of invaders, and the locals hardly noticed the difference, sort of or at least were ready for the event with contingencies.
https://www.alternatehistory.com/di...62HYPERLINKnewreply.php?do=newreply&p=4323062
https://www.alternatehistory.com/discussion/newreply.php?do=newreply&p=4323062
Hard to say what the make up of the languages. After many thousands of years, warfare does not tend to be an issue as people become settled. That is until a great new technology like the horse comes along. That Basque would have been in England seems silly unless there is evidence. More likely, there were pretty much unrelated languages all over. When a disaster comes up, that would be the main way for one group to expand, as the niches are different after the event and/or the rebound time is uneven for different locations.