The story, rather well known, would be this:
"This is exactly 1889.That summer King Umberto I with Queen Margherita, spent it in Naples, in the palace of Capodimonte, as a certain rule of the monarchy wanted, or to make an act of presence in the ancient kingdom of the two Sicilies. The queen was intrigued by pizza, which she had never eaten and had perhaps heard about from some writer or artist admitted to the court.But she could not go to the pizzeria so the pizzeria went to her; that is, the most renowned pizzaiuolo of the time was called to the palace, which was located at the Sant’Anna salita, a few steps from Via Chiaia. Don Raffaele came, saw and won, using the ovens of the royal kitchens, assisted by his wife Donna Rosa, who was then the real master of pizzas, the true author of the classic ones that were presented to the sovereigns (the chronicles of the time have informed us of everything) one with sugna which is a kind of lard, cheese and basil; one with garlic, oil and tomato and a third with mozzarella, tomato and basil, that is, with the colors of the Italian flag, which particularly thrilled Queen Margherita, and not only for patriotic reasons.
Don Raffaele, being a good public relations man, jumped at the chance and called this pizza " alla Margherita," the next day he put it on the list at his establishment and had, as you can imagine, countless requests…"
That would be the legend.
Only the real story is another
"The pizza alla margherita or pizza margherita, as it began to be called, passed for a novelty, an actual invention, while it is known to have existed before.
It was not considered among the most classic and important ones however, in Naples it was already being made. For example, for another queen, Bourbon Maria Carolina, who was fond of pizzas, so much so that she had wanted a special oven at court, in the palace of San Ferdinando. Caroline loved that white, red and green pizza very much; but perhaps, if she could have imagined that those would have been the colors of united Italy under another dynasty, which would have kicked hers out, she would not have been so enthusiastic about it anymore…"