Since the publication of A Christmas Carol in 1843 the name Charles Dickens has remained linked with Christmas. Dickens’s other Christmas stories have been largely forgotten, but the story of Ebenezer Scrooge’s conversion remains a hit all over the world. Why does this 19th-century writer continue to be such a large part of our Christmas experience, 140 years after his death?

As a great-great-great granddaughter of Dickens, I have always been very aware of him, particularly at Christmas – my much older cousin Cedric used to tell me stories of my great-great-grandfather, Henry Fielding Dickens (who died in 1933), reading A Christmas Carol to his extended family every Christmas. His reading abilities were apparently faltering and ponderous towards the end of his life, but he persisted on keeping the tradition going, despite the younger generation’s protestations.

I find it wonderful that Dickens holds centre stage in so many other families’ Christmases too. It was Prince Albert who introduced many of our favourite Christmas traditions to this country, yet most people credit the “invention” of Christmas to Charles Dickens. He remains associated as the founder of Christmas as we celebrate it, even in 2007. Christmas cards, plays and songs are often referred to as “Dickensian” when actually they are just vaguely Victorian, and make reference to snow. Dickens himself or his characters don’t even need to appear for the epithet to be applied.

The reason he resonates today is because he had such a personal sense of excitement about Christmas and because he wrote so superbly about human nature, in particular human weaknesses and triumphs. Each year the Charles Dickens Museum (www.dickensmuseum.com) in London is decorated as it would have been in Victorian times and the visitors revel in the atmosphere; many (and not only those from the UK) tell us that they look forward to coming every year as it is an essential part of their Christmas.

This year ITV1 is showing a new adaptation of The Old Curiosity Shop. Martyn Hesford’s adaptation provides all the excitement, drama, great costumes, big-name actors (Zoë Wanamaker, Derek Jacobi and Gina McKee among them) and everything else the Christmas viewer wants.

Yet Dickens’s story is not an easy one to watch, imbued with undertones of evil. Quilp’s abuse of his wife and his paedophiliac longings for Little Nell make him one of Dickens’s most vile villains. The selfishness of Nell’s brother and the unfortunately named Dick Swiveller (who, in the best tradition of Dickens, redeems himself) and the machinations of Sampson and Sally Brass make one want to shout, “He’s behind you”, but it is such compelling drama because Dickens plotted his chapters so well.

Dickens may not have invented Christmas as we know it, but he certainly popularised it, encouraging families who had largely ignored the celebrations to rediscover old traditions and begin new ones. In his documentary, Charles Dickens and the Invention of Christmas (Dec 23, BBC One, 3.40pm) Griff Rhys Jones asks whether Charles Dickens himself loved Christmas. He did, and he imbued the rest of his family with that excitement. His children and grandchildren carried on the tradition of keeping Christmas as an extra-special occasion and today you will still find members of the Dickens family (there are quite a few of us) appearing at Dickens festivals all over the world. For me, it is always a humbling experience to discover how much joy his works still bring to people and how excited people get at meeting a blood relative.

For the Dickens family, Christmas started on December 24, when the author would take his children to a toy shop in Holborn, Central London. They were allowed to choose one present each and presents for their friends. The festivities – including, as always in the Dickens household, much eating, drinking and dancing – continued until Twelfth Night.

As the children grew older, Dickens began staging lavish family theatricals at their home on Twelfth Night. Most members of the family – and friends including Wilkie Collins and Mark Lemon, the Editor of Punch – would act before an invited audience. Dickens even hired a policeman to stand outside the house to prevent gatecrashing. When the family moved to Gad’s Hill Place in Kent, Dickens would stage a Boxing Day sportsday, with hundreds of local people arriving to run races and play games for prizes. Dickens provided the prize money and various family members and house guests helped to judge the events.

As Rhys Jones notes, in 1867 Dickens spent Christmas Day on a train travelling through America from one speaking engagement to another. The man who had invented Christmas had become a performer earning money from helping other people to enjoy the fabled family Christmas he had encouraged them to expect. Just as the butcher is required to be open on Christmas Day at the end of A Christmas Carol, so the great author was providing others’ Christmas entertainment at the end of his life. It is no surprise that his Christmas cheer had become diluted – he was separated from his wife, infatuated with a young and increasingly uninterested mistress, five of his sons were living in far-flung countries with little prospect of his ever seeing them again and his favourite child, Katey, was married to a man whom Dickens knew made her unhappy.

He had returned to America at the age of 55, but he looked like an old man. He found the travelling exhausting and became dangerously ill. Yet it was not all bleak; Dickens was doing something he loved to do: reading and performing on stage, rekindling his adolescent dreams of becoming an actor. He was not with his family for Christmas, but he wrote of the warm hospitality he enjoyed from Americans, and how the most popular story he read out was A Christmas Carol.

A cathartic tale that leads the reader through feelings of sadness and empathy to an exuberantly happy ending is the stuff that keeps Hollywood in business. Charles Dickens knew that in the 1840s, and a wealth of actors, from Albert Finney to Kelsey Grammer, not forgetting The Muppets, have been kept busy recording versions of A Christmas Carol since the advent of the movie camera.

It has it all: a spooky ghost story, a heartwarming redemption and a great plot with a satisfyingly happy ending. It is this energy and his innate understanding of what the public wanted (and still wants) that keeps Charles Dickens at the forefront of Christmas, even in the 21st century.

Charles Dickens and the Invention of Christmas, Sun 23, BBC One, 3.40pm The Old Curiosity Shop, Boxing Day, ITV1, 9pm

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