At the end of her recent (and fabulously entertaining) New Yorker piece about Mary Queen of Scots the movie, Mary Norris throws in a little punctuation lesson about the comma (or lack of it) in the Scottish queen’s name. “Mary Queen of Scots – both the regal title and the movie title – takes no comma,” argues Norris. “There is more than one Mary; the title is restrictive. She is Mary the Queen – you know, like Cedric the Entertainer or Chance the Rapper. Off with the comma!”
But is Mary Queen of Commas right about this? Royal precedent seems to argue otherwise: let’s take Diana, Princess of Wales as a case in point. Following Norris’s reasoning, there are – and were – plenty of Dianas out there (just as there are lots of Marys) and Diana’s title was restrictive, just like Scottish Mary’s. So, according to Norris’s thesis, Diana like Mary should be comma-less. But Diana, Princess of Wales always had a comma, and she wore it proudly. The BBC, The New York Times, Encyclopædia Britannica and even The New Yorker all gave her one and continue to adorn her with a comma to this day. Go back a few centuries, and we have John (comma), King of England; cross the Channel, and we have Nero (comma), emperor of Rome, and Wilhelm II (comma), emperor of Germany –according to the Chicago Manual of Style, among others. Comma Queen also compares Mary Queen’s name to Chance the Rapper; however, the Scottish monarch was never Mary the Queen, and so Chance’s the makes all the difference.
Without delving too deeply into the whys and wherefores of restrictive and non-restrictive comma use, might Mary, Queen of Commas reconsider her ruling, based on long royal precedent?
— Louise, Queen of Glossophilia