One of the things that distinguishes The Netherlands from Iceland is Christmas. In the Netherlands they don't give presents on Christmas. They give presents in the beginning of December (5-6th) at Sinterklaas which is a winter festival. The character Sinterklaas is a bit like Santa Claus but is dressed like a pope and has little black helpers called black Petes (Zwarte Piet). The Christmases themselves are held in piece and quite with family. In Iceland there is no Sinterklaas. Everyone goes overboard buying expensive gifts that no one wants, at least not long. People stress themselves out doing preparations and trying to get into the holiday spirit. In Iceland the Christmas begins on December 24th, at six o clock when Christmas dinner is eaten, after which children open their presents. Then everyone sleeps for the rest of Christmas, exhausted after the preparations.
One possible explanation, of the jump start people in Iceland take on Christmas, is that in the old days it was traditional to give books at Christmas. If they packages are opened up at the beginning of Christmas, everyone has something to read so no one is bored during the beginning of the holidays.