Real deer were trained to pull the sleigh. The crew required months to complete the training which also allowed the deer to grow their antlers for the final filming. For shots where it was not possible to use the deer, sophisticated animatronic deer were used.
The role of the Ancient Elf was written with James Cagney in mind. However, with Cagney being very weak in his old age, the legendary actor could not adequately assume the role, despite the fact that he liked the film's overall idea.