Even before launching into the study of those few quatrains, and to clarify all that has been said and predicted concerning this birth, I must say that the expression Great Monarch, found at some places in the Epitre à Henri, roi de France Second [The Epistle to Henry, king of France Second, and also in the Centuries, is not accurat. It does not address the problem from the right angle and it reinforces a materialistic approach that veils even more the true purpose of the prophecies and the role this personage will play on the world scene in the coming months and years of the next millenium.
As with all other quatrains, those that pertain to this birth are strewn with allegory and symbolism, and the words do not always convey a true picture of what they represent.
It is true that Nostradamus adresses that personage with reverence and calls him 'Serenissime Majesté, [Most Serene Highness], but this, of course, is a stylistic device which Nostradamus uses to convey, in human terms, the vision he was witnessing, that of a person from which emanated light and radiance.
If we go back to an even earlier event, the Scriptures too had mentioned the coming of a King who would deliver his people from bondage, and when Jesus finally manifested as a spiritual teacher, he was confronted with the materialism of the churches and the people who were expecting a King, a temporal one, who would deliver them from the bondage of Rome. These expectations were so high in people's mind that his true message was only understood by those initiates [the Essenes] who had kept in mind the true purpose of his coming, and by those who had opened their heart his teachings.
Thus, Nostradamus predicts the coming of a personage whose role is identical to that of Jesus, and once again, and even before he manifests, he is considered as a future monarch, and, according to many exegetes, a king who will reestablish the monarchy in France.
Nothing of the kind will occur, of course, for based on my studies of the prophecies, the personage in question is a simple man whose main goal is to bring mankind back to a cosmic perception of the universe that surrounds us, which is, in fact, the return of the prodigal son [humanity] to his Father's house.
Leon Bloy describes this individual better than anyone in this excerpt I found in Maurice Poulin's book Le Grand Monarque, Messager du Verseau [P.43]:
[Translation] I often talked about someone whose coming will be unexpected, a stranger amongst all conceivable strangers. Never a man has been so unknown, so unexpected, so sudden. He will be astonishment itself! Is it possible that I am the only one that awaits and expects his coming?
Another excerpt from the same book where the author quotes Alice Bailey, british author and esoterist:
This 'rider on a white horse' is not an extraplanetary life, but essentially someone like us, whose nature, human and animal, merges into the divine, inspired by a divine and cosmic principle just as the Christ was informed by the love of God...That rider is a human being that has attained a predestined goal and, - through love and understanding of human nature - has remained in the secret place of revelation, awaiting the time when he will finally lead his people to a triumphant victory.
Here, the meaning is clear enough and the victory in question has nothing to do with the armies of the world. It is a victory over the limitations, a victory over greed, hate and intolerance.
The author also quotes a certain Robert Charroux:
The futur Buddha will come from the West and the North and will be the Kalki-Avatara of the Hindus, which, acording to the author, could indicate any latitude above the 44th parallel...
If we take a closer look, there seems to be a direct link between the Letter and the Epistle, both of them being veiled messages that Nostradamus adresses to an individual of the future who will be born, according to the prophecies, at an undefined period of our own history.
Written three years after the Letter, the Epistle seems to confirm the theory of a link between the two missives and a similitude between the Cesar of the Letter and the Most Serene Highness of the Epistle that made such an impression of the prophet.