For Catholics, Christmas traditions are not mere rituals. They hold a precious truth — that God, the eternal Word, truly took human flesh and came to live among us.

Those who seek to downgrade the specifically Christian significance of Christmas need to know about the company they are keeping.

The Puritans tried to abolish Christmas. In 17th-century England, Oliver Cromwell made it illegal to mark the feast — and even to eat mince pies. He and his followers disliked the very name — Christ's Mass — because, of course, it was deeply Catholic. And the traditional mince pie — a small oval or circular pie with crinkly edges — had Christian significance: It was meant to represent the manger, with Christ as the sweetness inside.

There is some historical evidence that the origins of Thanksgiving owe something to the Puritan anti-Catholic tradition: Get people feasting on turkey and cranberries in November and gradually this will squeeze out all that papist Christmas nonsense. Fortunately, the American nation had too much common sense to let that idea take hold: Thanksgiving is celebrated in style, and Christmas follows a month later with an even bigger and cheerier round of feasting.

A law passed in Cromwell's day made Christmas an ordinary working day in Britain, and people were fined if they took the day off work or encouraged their employees to do so. Later, there was an attempt to abolish the name “Christmas” and replace it with “Christ-tide.”

The restoration of the monarchy in England — with Charles II after Cromwell's death — also naturally meant the restoration of Christmas. Perhaps that is why there has always been a link between the monarchy and Christmas in England. The queen's annual television address to the nation — usually broadcast at 3 p.m. and repeated later — is a major part of a British Christmas, and some families do not open their presents until “after the queen.”

The Glastonbury Thorn — said to have grown from the staff planted in the ground by Joseph of Arimathea when he arrived on the shores of Britain after leaving the Holy Land — blooms every year at Christmas, and a sprig is sent to the queen.

Elsewhere in Europe, in traditionally Catholic lands, Christmas Eve has always been marked with beautiful traditions and ceremonies, all associated with the idea of Advent as a season of penance and the birth of Christ as a time of joy. The traditional Christmas Eve dinner is fish. In Germany, and in much of Eastern Europe, it was always carp — because Christmas Eve was a day of fasting and abstinence from meat. The next day saw the roasting of a goose — meat was allowed at last.

The idea that we mark a feast day on the night before it is now very familiar to us because for the past few decades we have had Saturday vigil Masses that fulfill our Sunday obligation. Of course, midnight Mass at Christmas is part of the same tradition — all originating in the Jewish idea that the day begins as dusk falls on the evening before — hence the traditional Jewish Friday-night celebration of the Saturday Sabbath.

We all know — or ought to know — that Santa Claus was originally St. Nicholas and that he is linked with Christmas simply because St. Nicholas' Day falls in December. But perhaps children do not know that the little golden-colored mesh bags of chocolate coins they get in their Christmas stockings have a special link with St. Nick — he dropped three bags of gold down the chimney of a poor household where there were three girls who had no money for dowries and could not get married.

St. Nicholas always does things in threes — there is a story of his rescuing three small boys from being kidnapped — because, in real life, he was the bishop who robustly defended the Trinity against the teachings of the heretic Arius in the fourth century. We have seen the Arian heresy revived in our own day — with the assertion that Christ was not truly divine, but merely a very good man — so Catholics have good reason to honor St. Nick as a saint with a very modern message.

Christmas is about the Incarnation. It wasn't just the Puritans, but the early Reformers who were troubled by the very vivid Catholic understanding of this mystery. St. Robert Sothwell — a noble and heroic English martyr who met his death on the scaffold at Tyburn in the reign of Elizabeth I — wrote a wonderful poem, “The Burning Babe,” which exemplifies the great reality of God made man, the deity actually living among us as a helpless baby. This poem became immensely popular even in his own day; it was passed around and printed anonymously. Today, it is sung and enjoyed by many people every Christmas, as it forms part of Benjamin Britten's “Ceremony of Carols,” a popular feature of school and college Christmas concerts.

When we celebrate Christmas, we should not apologize for our traditions. Whether we are roasting a plump fowl, or making mince pies, or gathering on Christmas Eve to watch the first star appear (a Polish custom) so that our celebrations can begin, we are united with our ancestors. In times past, opponents of the Church have tried to crush Christmas and failed. They will fail again. As Cromwell and the Puritans became history, people tended to recall only the well-intentioned, comic or simply whimsical aspects of their lives. Some day, our descendants will doubtless do the same as they laugh over attempts to ban the public display of Nativity scenes or the use of “God bless you” on public-school premises. Meanwhile, we should enjoy ourselves, and — in public and in private — have a merry Christmas.

Joanna Bogle writes from London.