Santa Claus

Santa Claus — also known as Father Christmas, or Jeff (TV: A Christmas Carol, COMIC: Holiday Special) — was a legendary figure who distributed presents to good children on Christmas morning under their trees. He played an important part in the Christmas tradition on the planet Earth. Much like other Earth legends such as King Arthur, sources heavily contradict and dispute each other on the topic of whether Santa was a real figure or a fictional entity.

According to the Thirteenth Doctor, children all over the world believed in Santa, and they all wrote him letters with their Christmas wishes. (COMIC: Holiday Special)

Profile
Santa maintained a workshop where he created toys. It used to be located at the North Pole, but due to the aeroplanes which began flying over it in the 20th century it became very noisy, so he moved it to the Christmas-land. (COMIC: A Christmas Story) In order to deliver presents to all children in a single night, Santa used time loops and clones of himself. (PROSE: The Man Who (Nearly) Killed Christmas)

He was married to Mary Christmas. (AUDIO: Iris Wildthyme and the Claws of Santa)

Origins
Santa Claus was based on the Saint Nicholas of Myra, a 4th century bishop from Asia Minor. (AUDIO: Better Watch Out, Fairytale of Salzburg)

Father Christèmas of Faction Paradox claimed that the jolly character of Father Christmas was created by Ben Jonson in the early 17th century to mock Christèmas following a failed deal between the two. The Ministry of Insinuation were displeased that the idea of Father Christmas went viral. (PROSE: Weapons Grade Snake Oil)

Astrolabus claimed to be Santa. (COMIC: Voyager)

Biography
The First Doctor visited Santa Claus in his workshop and helped save Christmas. (COMIC: A Christmas Story)

The Second Doctor warned Santa of a future where the toy workshop spanned over two thousand worlds and the fabric of space was being torn by his time looping. A solution was found involving a fleet of robot Santas and newly calculated, more stable wormholes. (PROSE: The Man Who (Nearly) Killed Christmas)

The Third Doctor and Sarah Jane Smith travelled to New York City in 1822, where they met Saint Nicholas. Clement C. Moore watched them from his window, and then sat down to write Twas the Night Before Christmas. (PROSE: A Visit from Saint Nicholas)

Santa helped Iris Wildthyme save Panda from Mary Christmas. (AUDIO: Iris Wildthyme and the Claws of Santa)

Torchwood One helped deal with his existence. (PROSE: Trace Memory)

He met the Eighth Doctor and Lucie Miller at Nadir Motorway Service Station in 2008, and he was depressed that people weren't believing in him any more. They took him with Anty Pat to Lucie's parents' home. Though it later turned out he was likely just an old man who played Father Christmas at shopping centres and had lost his job as he was apparently too old, he was offered a job because of his people skills at a hospital. (AUDIO: Death in Blackpool)

At some point, the Tenth Doctor and Donna Noble met him, after a skirmish with Roboforms and snowmen. He replaced the Doctor's sonic screwdriver. (PROSE: Dr. Tenth: Christmas Surprise!)

A shared-dream version of Santa Claus and his elves Ian and the Wolf, as well as his flying reindeer, appeared in a collective dream shared by the Twelfth Doctor, Clara Oswald, Shona McCullough, Ashley Carter, Albert Smithe and Rona Bellows, who were being fed on by dream crabs. (TV: Last Christmas) He first appeared to the Doctor when he entered his TARDIS, and told him that Clara was not happy with their recent separation. (TV: Death in Heaven) According to the Doctor, Father Christmas represented their subconscious minds trying to break free of the induced dream state which was killing them. He appeared to know things about them, like that Shona liked My Little Pony, and also claimed to have watched over and taken care of everyone sharing the dream "from Christmas to Christmas". The group of six rode on Santa's sleigh over London as they one by one woke up again into the real world. He later appeared again to the Doctor, causing him to realise he was still in a dream and to wake up for real — although as the Doctor and Clara Oswald reunited in the real world and resumed their adventures together, a tangerine, one of Santa's calling card gifts, was seen on her windowsill. (TV: Last Christmas)

One Christmas Eve, the Thirteenth Doctor lent Santa her TARDIS when his sleigh stopped working. (WC: 'Twas the Night Before Christmas)

Impersonations
The Fourth Doctor dressed as Santa and sneaked into the Brigadier's house with Romana II in order to leave him a Christmas present. (PROSE: Special Occasions: 3. Better Watch Out, Better Take Care)

On Christmas Eve 2006, Rose and Mickey Smith encountered dangerous "pilot fish" disguised as Santas. (TV: The Christmas Invasion)

On 25 December 2007, the same robots, now under control of the Empress of the Racnoss, attacked Donna Noble and Lance Bennett's wedding reception. (TV: The Runaway Bride)

On 24 December 2008, the Eighth Doctor, Lucie Miller and Haygoth ran into a drunken man whose job was to impersonate Santa Claus. However, he was fired due him being "too old". (AUDIO: Death in Blackpool)

Danny Pink dressed as Santa Claus on Christmas Day in a dream crab-induced dream Clara Oswald was in. When she asked what day it was, he briefly joked that it was Easter and that he was dressed up as "Father Easter". Danny was in reality dead at this point in her timeline. (TV: Last Christmas)

Krampus took on Santa's appearance while under the guise of "Mr. Henderson". (COMIC: Holiday Special)

Behind the scenes

 * Santa Claus and Father Christmas have different origins and are technically once considered different individuals. However, as in modern day, the character portrayed by Nick Frost in the television stories Death in Heaven and Last Christmas is identified in the closing credits as Santa Claus, and referred to in dialogue in Last Christmas with both names. A Christmas Carol also has the Eleventh Doctor describe the "fat fella" with both names.
 * In An Adventure in Space and Time, Verity Lambert (Jessica Raine) describes the First Doctor as "C. S. Lewis meets H. G. Wells meets Father Christmas".
 * According to writer Steven Moffat, "Everything except the very last scene" of Last Christmas "is a dream" and "[t]he tangerine represents the fact that Santa Claus obviously stage-managed the whole thing to get the [Twelfth] Doctor and Clara back together."

Portrayals in other media
William Morgan Sheppard voiced Santa in the 2009 Disney animated TV special. He reprised the role in the 2011, as well as in the 2010.

Jim Broadbent has played Santa twice: voice only in the 2011 animated film (which also featured Bill Nighy as "Grand-Santa") and on screen in the 2014 film  (also featuring Jodie Whittaker, Warwick Davis, Nonso Anozie, Perry Benson, and Matt King).

Brian Blessed has played Santa at least three times: episode "Christmas" (2012; voice only),  episode "Pranks and Presents" (2013), and  (starring Alexander Armstrong) episode "The Snowman Cometh" (2015; voice only).

Hugh Bonneville voiced Santa in the 2015 animated TV special (also featuring Jennifer Saunders and Rob Brydon).

Matt Lucas voiced him in the 2018 animated special Aliens Love Underpants And... Panta Claus.