The British "Christmas No. 1" has been a tradition for over half a century. Starting in 1952, the top song on the British singles chart has been a coveted spot each and every Christmas. Christmas No. 1 alumni include The Beatles, Queen, Ed Sheeran, and more.
While some Christmas No. 1s have indeed been Christmas songs — "Do They Know It's Christmas?" by Band Aid II in 1989, for example — they don't have to be.
The Spice Girls have been awarded the most consecutive Christmas No. 1s, with three victories in the '90s. However, The Beatles hold the title of most Christmas No. 1s with four.