Many children write letters to Santa Claus, but very few receive such lengthy replies as J.R.R. Tolkien’s children did. Starting in 1920, when the eldest, John, was three, each year the Tolkien children received an envelope in the post, complete with North Pole postmarks and stamps, containing a letter written in Father Christmas’s own shaky hand. The first letter was just a brief note, but soon Father Christmas was writing lengthy missives to the Tolkien children, telling them about events at the North Pole – largely humorous stories involving his sidekick, the North Polar Bear. Sometimes, the North Polar Bear’s antics explained the absence of certain presents the children had asked for (as when the N.P.B. fell asleep in the bathtub with the taps running, flooding F.C.’s storerooms!). Other times, events in Father Christmas’s life mirrored events in the Tolkien family – for instance, as the Tolkien family was getting ready for their move from Leeds to Oxford in January 1926, the 1925 Christmas letter told of an accident that destroyed the roof of Father Christmas’s house, forcing him to move to a new house himself.

The letters themselves were lovingly created works of art, with different handwriting and colours of ink for Father Christmas, the North Polar Bear, and later Father Christmas’s secretary Ilbereth. But they were also always accompanied by drawings (often drawn by the North Polar Bear, whose real name, it was eventually revealed, is Karhu).

In the later years, as the children got older, Father Christmas’s adventures started to get a little more serious. In the 1930s (around the same time The Hobbit was being written), he had a number of adventures involving goblins. As time went on, the cast of characters expanded, with the North Polar Bear’s nephews, the Red and Green Elves, the Snowmen, and others. 

The letters continued until 1943, when Priscilla, the youngest, was 14. They were posthumously published in 1976, edited by Christopher Tolkien’s wife Baillie. The original edition omitted some of the letters deemed to be less interesting, but a complete version – including every letter and every drawing – was published in 1999.