Modern silk road, called trans-siberian railway, the railroad through Russia. Factories and cities were built next to the railroad. A lot of other nations live in russia, but they are not indo-europeans, and much smaller in numbers.

There are 25 regional official languages in russia, only 2 of them indo-european: Osetian and Ukrainian. Most others are Turkic and Uralic https://en.m.wikipedia.org/wiki/Languages_of_Russia

Also this map is shitty, as it doesn’t show what percentage of people speak the language, 51% looks the same as 99%.