(not so) interesting fact: Russians celebrate new years much like we celebrate Christmas (gift giving, family meal etc;)

This is due to the Soviet Unions downplaying of religion, but understanding the need of a yearly get-together.

So, my girlfriend celebrates NYE as if it were Christmas, Christmas is seen as "not really important" and she didn't even have a concept of Christmas being on Dec 25th (which, consequently was when she was born herself)

Russians currently celebrate Christmas by being mostly drunk between Orthodox Christmas and Twelfth Night.

It's basically the slavic orthodox countries that use the old calendar, plus certain groups that have more or less broken out of other churches. The monasteries on Athos also use the old calendar, even the monasteries that belong to new calendarist jurisdictions. A fun fact is that visas to Athos, which is a semi-autonomous island in Greece where only men are allowed (not even female animals!) and that prince Charles loves, are issued in the Julian calendar.

It's worth noting that even most new calendarists, like the Greeks, still celebrate Easter at a different date than the Catholics.

The calendar question is extremely infected and especially the Russians consider it a very crucial issue.

https://en.wikipedia.org/wiki/Mount_Athos

At least in the U.S., the Antiochian and Greek Orthodox churches primarily use the Gregorian calendar (e.g., Christmas is on Dec. 25). However, Pascha and its related feasts are still determined using the Julian calendar which happened to fall on the same day as the Western Easter this year (Apr. 16).

Christians agree that Easter is computed using a lunar calendar, however, various sects use different methods for computing lunar leap months. Passover is also on the lunar calendar.

Easter (or Pascha/some derivative as it's called in most non-English countries - which comes from Passover) is basically Passover + a bunch of days (remember the story of the Crucifixion then Resurrection).

My mistake. For some reason I was thinking there was still some component of the Julian calendar used with the calculation even though it is lunar based.

Curiously, January 7 is also when many Spanish families exchange gifts, supposedly as a celebration of the arrival of the Magi/Three Wise Kings (who brought gifts to Jesus).

This is much to the annoyance of Spanish kids with foreign friends :)

Yes, but that is a coincidence. Russians celebrate Christmas on December 25th like everyone else (except some norther Europeans, we celebrate on the eve), it's just that their view of when it is December 25th differs.

Yes, it's a coincidence, that's why I find it curious :)

Christmas in Russia is celebrated on 7 January

My point was that no, the holidays are celebrated on the same dates throughout the Christian world, but depending on which calendar you use those dates fall on different days. Today for example it's August 10th in many Orthodox churches, while most others would say it's the 23rd.

That holiday is Epiphany, which is a separate holiday (and I believe actually falls on the 6th of January on the Gregorian calendar).

It's amusing that Twelfth Night is so little known, despite the play, the "12 days of Christmas", and so on.

I suspect if you asked most people when the 12 days of Christmas are, they'd say they were December 14-25 (or maybe even 13-24). After all, that's when you buy the presents!

Nah it depends. Romania is also an Orthodox Christian country but uses the Western calendar. They still have Easter on the same day because that's calculated separately, but they celebrate Christmas on different days - Dec 25th vs Jan 7th.

Not all. Some have switched to Gregorian calendar.