One of the historic advantages of Western Europe was that it was conquered by the Romans in ancient times — a traumatic experience in itself, but one which left Western European languages with written versions, using letters created by the Romans.  Eastern European languages developed written versions centuries later.

Literate people obviously have many advantages over people who are illiterate.  Even after Eastern European languages became literate, it was a long time before they had such accumulations of valuable written knowledge as Wester European languages’ centuries earlier head start.

Even the educated elites of Eastern Europe were often educated in Western European languages.

None of this was due to the faults of one or the merits of the other.  It’s just the way that history went down.

– Thomas Sowell