The name Santa Claus is a US version of Sinter Klass, which it the dutch for Saint Nicholas. Saint Nicholas was a Christian saint from the early church in what is now Turkey (Then a greek speaking part of the Roman Empire). He was a bishop and was renowned for giving anonymous gifts to poor people. His feast day is December 6th when, in some countries, people still give presents to children from St Nicholas.

However, this present giving was moved to Christmas by some protestant reformers so Saint Nick went with it.

The tradition of the Christmas Tree started in Europe and is first recorded in the 16th century, well into the Christian era. There is NO evidence at all of any connection to paganism.

The first Christmas trees were put up on Christmas Eve and were decorated with fruit and nuts (now replaced by glass baubles and candy). Christmas Eve used to be counted as the Feast of Adam and Eve. The connection is obvious - the Christmas tree represents the tree in the Garden of Eden.

The birth of Christ, the second Adam, transforms the tree from a symbol of our fall to a symbol of our redemption.