How And When Did The Tradition Of Exchanging Christmas Gifts Start?

Christmas traditions are deeply rooted in the  Ancient Yule Rituals. People all over the planet celebrate the winter solstice, in the northern Hemisphere it is celebrated on Dec 21and in the southern hemisphere celebrates it on June 21. Why do we celebrate, when we really don't know when Jesus was born and that has never been documented,the only thing we know is it started about 4000 years ago.
We first see Christmas mentioned in the early 3rd century and then in the early 4th century the celebration of christ began wide spread. I am not going to go in deep history of the events since that would take up alot of time but I will say that in the Pagan community Dec 25 is a wide spread holiday to celebrate the coming of the  Babylonian Queen of Heaven and in Rome the celebration was taken and given the name Of Christ.  This celebration was invented to compete against the pagan celebrations of December. The 25th was not only sacred to the Romans but also the Persians whose religion Mithraism was one of Christianity's main rivals at that time. The evergreens,mistletoes and the holly is sign of eternal life,regeneration and rebirth.
Alot of Christmas traditions were celebrated centuries before the Christ was born. Here is a list of these events: 12 days of Christmas, the bright fires, the yule log, the giving of gifts, carnivals(parades) with floats, carolers who sing while going from house to house, the holiday feasts, and the church processions can all be traced back to the early Mesopotamians.
As for the  tradition ,it's interpretation remains the same over the centuries and all stems to the gift of giving and that is what is most important no matter what religious identity you paint yourself with.

It began the night that Christ was born. The 3 kings brought gifts to the baby Jesus, I believe it was gold, frankensence and mir(mur) that were brought to the baby Jesus the night he was born.

The dutch people might have the answer to this as there Christmas is slightly different to most