In Good King Charles's Golden Days

A much commoner theatrical product is the historical romance,
mostly fiction with historical names attached to the stock
characters of the stage. Many of these plays have introduced their
heroines as Nell Gwynn, and Nell's principal lover as Charles II.
As Nell was a lively and lovable actress, it was easy to reproduce
her by casting a lively and lovable actress for the part; but the
stage Charles, though his costume and wig were always unmistakeable,
never had any other resemblance to the real Charles, nor to anything
else on earth except what he was not: a stage walking gentleman with
nothing particular to say for himself.

Now the facts of Charles's reign have been chronicled so often by
modern historians of all parties, from the Whig Macaulay to the
Jacobite Hilaire Belloc, that there is no novelty left for the
chronicler to put on the stage. As to the romance, it is
intolerably stale: the spectacle of a Charles sitting with his arm
round Nell Gwynn's waist, or with Moll Davis seated on his knee,
with the voluptuous termagant Castlemaine raging in the background,
has no interest for me, if it ever had for any grown-up person.

But when we turn from the sordid facts of Charles's reign, and from
his Solomonic polygamy, to what might have happened to him but did
not, the situation becomes interesting and fresh. For instance,
Charles might have met that human prodigy Isaac Newton. And Newton
might have met that prodigy of another sort, George Fox, the
founder of the morally mighty Society of Friends, vulgarly called
the Quakers. Better again, all three might have met. Now anyone
who considers a hundred and fiftieth edition of Sweet Nell of Old
Drury more attractive than Isaac Newton had better avoid my plays:
they are not meant for such. And anyone who is more interested in
Lady Castlemaine's hips than in Fox's foundation of the great Cult
of Friendship should keep away from theatres and frequent worse
places. Still, though the interest of my play lies mainly in the
clash of Charles, George, and Isaac, there is some fun in the clash
between all three and Nelly, Castlemaine, and the Frenchwoman
Louise de Kéroualle, whom we called Madame Carwell. So I bring the
three on the stage to relieve the intellectual tension.