Why do so many countries celebrate Christmas 25th December?

Question

Here in our Nordic countries we celebrate it 24th December on Christmas eve.

Answer 1

Whatever the truth is, we celebrate the day Christ was born and it will always celebrated on 25th....

Answer 2

In Brazil we celebrate Christmas on the night of the 24th

Answer 3

I think it has something to do with the position of the sun on the horizon but I'm not sure about that.

Answer 4

Because Rome's influence spread quite a ways (and I mean Rome, not the Vatican).

Answer 5

I think it has something to do going back to the Papacy setting up December 25th as the day to celebrate Christmas.