The Twelve Days of Christmas begin on Christmas Day; the period before that is Advent, the time of preparation for Christmas. The twelve days of Christmas end on Epiphany, the day that the Three Wise Men came to pay homage to the Child Jesus.
Because so many people, especially in the United States, treat the Advent season as the "Christmas season" however, the actual Christmas season gets lost. By the time Christmas Day comes, people are ready to pack up the decorations, and the tree—which they might have put up as early as Thanksgiving weekend—is probably past its prime.
If we were to revive the older tradition of putting up the Christmas tree and decorations closer to Christmas, then we could celebrate Advent to its fullest—and in keeping our decorations up after Christmas Day, we might find a renewed sense of joy in celebrating all Twelve Days of Christmas.
When I have my own apt, I delay all things Christmas to the month of December, usually putting up my tree the first weekend in December. This nips what I call "Christmas creep", in the bud. Christmas creep is the commercialization and consumerization of Christmas which seems to start earlier and earlier on the calendar each year, and seems to creep up into more and more preceding months every year, creeping into November, October, September, August, July . . . Nope not with me it doesn't. The only thing you should be doing in those months concerning Christmas, is funding your monthly budget category for Christmas. I confine all things Christmas to begin in December (music, decorations, gifts, visits, appointments, etc). November is Thanksgiving, and December is Christmas.
But as far as ending Christmas, I celebrate Christmas through Epiphany. When I have my own apt, I usually take down my tree on the weekend following Epiphany.
Epiphany is another one of those nebulous, not-sure-what-this-means Christian holidays that I grew up knowing absolutely nothing about. The other dictionary meanings for the word, was what I was familiar with. So as an adult, one of the first Christian holidays I reclaimed, was Epiphany.
Underneath my tree I always put up a nativity scene, with a caravan of camels and wisemen coming in from the wings, as told in the Bible in Matthew 2.
The Twelve Days of Christmas are the festive days beginning Christmas Day, December 25th. This period is also known as Christmastide and Twelvetide. The Twelfth Night of Christmas is always on the evening of 5 January, but the Twelfth Day can either precede or follow the Twelfth Night according to which Christian tradition is followed. Twelfth Night is followed by the Feast of the Epiphany on January 6th. In some traditions, the first day of Epiphany (January 6) and the twelfth day of Christmas overlap.
Over the centuries, differing Christian denominations have had different customs, time frames and interpretations. St. Stephen's Day (or Boxing Day), for example, is 26 December in the Western Church and 27 December in the Eastern Church. 28 December is Childermas or the Feast of the Innocents.
So the 12 days of Christmas is a season of feasts (in counterbalance to the fasting during Advent). Here are the twelve feasts of The Twelve Days of Christmas:
Dec 25: The First Day of Christmas: Christmas Day
Dec 26: The Second Day of Christmas: Saint Stephen, Deacon and Martyr
Dec 27: The Third Day of Christmas: Saint John, Apostle and Evangelist
Dec 28: The Fourth Day of Christmas: The Holy Innocents
Dec 29: The Fifth Day of Christmas: St. Thomas Becket, Bishop and Martyr
Dec 30: The Sixth Day of Christmas: The Holy Family
Dec 31: The Seventh Day of Christmas: Saint Silvester I, Pope
Jan 1: The Eighth Day of Christmas: Solemnity of Mary, Mother of God
Jan 2: The Ninth Day of Christmas: Ss. Basil the Great and Gregory Nazianzen, Bishops
Jan 3: The Tenth Day of Christmas: The Most Holy Name of Jesus
Jan 4: The Eleventh Day of Christmas: St. Elizabeth Ann Seton
Jan 5: The Twelfth Day of Christmas: Twelfth Night; St. John Neumann, Bishop
Jan 6: Epiphany, the 12th day after Christmas, falls on Sunday, January 6, 2013. Epiphany celebrates the visit of the three kings or wise men to the Christ Child, signifying the extension of salvation to the Gentiles (the wise men represent the Gentiles). Epiphany also signifies the day when the manifestation of Christ's glory was realized, i.e. they had an epiphany.
So today is Dec 29th . . . and it's perfectly appropros to still wish every one a Merry Christmas, through all twelve days of Christmas. So Merry Christmas every one!