One of the differences between East European and Central European culture/tradition is the fact that Eastern Europeans start celebrating Christmas today! It's because Orthodox Churches follow the Julian calendar: en.wikipedia.org/wiki/Julian_calendar
We follow the Gregorian calendar: en.wikipedia.org/wiki/Gregorian_calendar
Spain, Portugal, the Polish-Lithuanian Commonwealth, and most of Italy implemented the new calendar on Friday, 15 October 1582, immediately following Julian Thursday, 4 October 1582.
The Julian calendar is much older than the Gregorian, it was used in the first centuries of Christianity.
Orthodox Christians during Christmas Eve supper share prosphora instead of Christmas wafer: en.wikipedia.org/wiki/Prosphora
According to Wikipedia Christmas wafer originated in Poland and is used only in Central Europe: en.wikipedia.org/wiki/Christmas_wafer
So, for Orthodox Christians the New Year is still to come! Russians celebrate the New Year twice! :D
And something that is completely weird for Poles - Russians have Christmas tree and they exchange presents on the New Year!:
Btw, there's about 550-600 000 Orthodox Christians in Poland.
In case there are any Orthodox Christians on this forum from whichever country, I wish you:
С Рождеством Христовым!