Holy Scripture correctly records that there is nothing new under the sun. It currently seems to be a matter of considerable moment at the Court of St James's that a Harry and a Megan should no longer be styled 'Royal Highnesses'.
A very similar question caused great acrimony when 'Edward VIII' discovered that his American divorcee would be denied the title of Her Royal Highness. He never stopped nagging about this restriction. Happily, an admirable woman, Elizabeth Bowes-Lyon, saw to it that there was no weakening. Wallis Simpson died with all the shame of being a mere duchess.
But there is something odd here. In the Middle Ages, the upper crust of the political class ... Kings, Dukes, Archbishops ... all were addressed as "Your Grace". The sharp distinction between a Monarch ruling in Majesty, and the slightly inferior Mighty, was not so acutely felt; just as the word 'Prince' was employed differently.
And Ms Markle is still the Duchess of Sussex. If she and her husband, as we have been informed, will "not be using" the style HRH, well, that leaves them as "Their Graces". I am not sure how easy it is to suppress a dukedom ... Acts of Attainder have not been much heard of since Mr Churchill floated the jolly idea of hanging German War Criminals simply by virtue of a British Act of Attainder.
I have no doubt I shall be dead when ... if ever ... the archives of the 1930s are made fully public. I am pruriently curious to know how close we may have been in the 1940s to having 'King Edward VIII' and 'Queen Wallis' crowned in Westminster Abbey under the affectionate eye of Herr von (seventeen carnations) Ribbentrop, or whoever else might have been the Fuehrer's High Representative in a ruined Britain reduced to de facto vassal status by a dominant Nazi Germany. (I suppose another candidate for that role might have been His Royal Highness SS Gruppenfuehrer Prince Charles Edward of Saxe-Coburg und Gotha, but for the Titles Deprivation Act of 1917 Duke of Albany, Earl of Clarence, and Baron Arklow.)
It really doesn't bear thinking about what might have happened if Pearl Harbour had never saved our bacon by bringing the US of A into the European War. But quite possibly it might have included 'Edward VIII's' constitutional experts taking a leaf out of Henry VI's book, and proclaiming his "readeption" of the Crown.
Now that we have an Etonian First Lord of the Treasury, when will Henry VI be canonised?