|King William IV|
As some people may or may not realize, the English monarch’s birthday is not always celebrated on the actual anniversary of his or her birth. Queen Elizabeth II, who was born on 21 April 1926, most recently celebrated her “official” birthday on 16 June 2012.
So it was in the case of the reigning monarch, King William IV, in the time of Scandal Wears Satin. In 1835 his official birthday—and the Drawing Room that caused so much anguish to one character—was 28 May.
~~~In leaving the great quadrangle, and passing along in front of the tower, upon the quay, my attention was arrested by something like fifty very small brass pieces, not more than two feet in length, shaped like a howitzer, and placed in a line, a few feet apart, and having the appearance of being loaded, and ready to be discharged. It occurred to me instantly that I had often, when I was a boy, heard of the firing of the Park and Tower guns, and as this was done only on great occasions, I thought they must be very great guns, of course. Upon inquiry, I found that these squibs were to be let off at one o'clock, in honor of the King's birth-day. I do not know that a sense of the ludicrous ever came over me so powerfully as at that moment. However, I congratulated myself upon happening to be in London on the king's birthday, when I was further informed that it was not exactly and literally so", for he was born in the autumn, and not in the spring, and upon further inquiry, I ascertained that it is one of the rare prerogatives of the British monarch, to choose his own birthday, according to his own royal pleasure and convenience. This year it occurred in the month of May. Next year it may happen earlier or later, just according to the high behest of the throne. At one o'clock, I presume, the Park and Tower guns were fired, though I was not so fortunate as to hear them, and in the evening there were splendid illuminations, in St. James Square and other parts of the metropolis. —Supplement to the Connecticut courant, Volume 4, 1835
Illustration, Sir Martin Archer Shee (1769-1850), King William IV, from Wikipedia