The history of the lead up to the festive season
The Adventszeit are the four weeks (each concluded with an Adventssonntag) before Christmas. It is customary to display an Advent Wreath on a table instead of being hung on the door. Only the number of candles on the wreath is lit that correspond with the count of the Advent Sundays having passed. Consider the old nursery rhyme:
Advent, Advent,A candle is alightFirst one, then two, then three, then four.Then the 'Christ Child' is at the door.
Instead of the last line, you may find the rather sarcastic variation:
And when the fifth candle is alight,then you overslept and missed Christmas.
Saint Nicholas is based on a bishop of Myra (in what is today Turkey), who lived in the 4th century AD. He is said to have provided charities to people, in particular children. He is usually portrayed in a bishop's habit with a Mitre and a red coat.
In the catholic tradition, on the eve before December 6th, St Nikolaus comes to the children's houses, accompanied by his servant Knecht Ruprecht (sometimes called Krampus). He reads out of the 'Golden Book' all good and bad attributes of the kids and the generally well-behaved children will get small presents (traditionally fruit, nuts and cookies). But the bad ones receive a birching from Krampus ... and the really bad apples are taken away in Krampus' big sack.
In protestant regions, children will put a pair of shoes, well cleaned, or a dish in front of the houses's front door for Nikolaus to fill small presents in, on the evening of December 5th. The next morning, they find some chocolate, oranges, nuts or similar there.
Christmas is celebrated on the evening of December 24th - the Heiligabend. As a child, you will be told to remain in your room from late afternoon on, because the Christ-child (das Christkind) will come tonight. Without you knowing (or something like that), your parents prepare the Christmas Tree (Weihnachtsbaum). Choice of ornaments varies dramatically from household to household, ranging from all-natural and home-made with wax candles to the plastic tree with flickering electric lights.
After sunset (maybe 6pm) you are asked to join your parents. This is typically done with a special little bell (Gloeckchen) that serves only this one moment in the year. After the Bescherung (when the gifts are unwrapped) the special Christmas Dinner is served.
In a variation, dinner may be served before the Bescherung in the room different from where the Weihnachtsbaum is. When the family has almost finished dinner, one of the parents will sneak out and ring the little bell. The other parent exclaims: "Oh, the Christkind was just here!," which is your cue to open the door and for the first time you see the Weihnachtsbaum - and all the presents underneath. Then everyone wishes everybody else a "Froehliche Weihnachten;" you open your presents and play until you fall asleep under the tree. This is the one night in a year, when you do not have to go to bed early.