François Velde, the Webmaster of the magnificent internet web site "Genealogy of the Royal Family of France: Descendants of King Hugues Capet," has written me:
[The Cardinal de Bourbon] is not in the official lists of French sovereigns. The question of who was the legitimate king in the interval 1589-93, when the individual designated by ordinary succession laws [Henri de Navarre] was not Catholic, is an intriguing one. But if one resolves it by saying that it was the next person [who was] in line of succession and Catholic, then one is led to difficult problems: for example, who was king after the death of the cardinal de Bourbon and before Henri IV's conversion? How did that person lose his throne in 1593 when Henri IV converted? Logic would dictate that someone [who is] passed over for succession is excluded once and for all, but no one nowadays disputes that Henri IV was, at least after 1593, the legitimate king of France; so he was clearly not passed over.
I touch on some of those issues in the debate of legitimism vs. orleanism (the 1589-93 period is an interesting one for those who contend that the succession laws in France were not God-given, eternal and immutable, but rather shaped by events over time).
I replied to him:
Thank you for your reply. You make good points. Of course, one might say that the Restoration-era King Charles's choice of "X" rather than "XI" is what's really dispositive of the issue. I think, though, that your site should at least indicate that the Cardinal de Bourbon claimed to be King Charles X between 1589 and 1590.
In answer to your points, I guess I would try to argue that because the Cardinal de Bourbon was the true successor of King Henri III, both by France's law of succession (as it was interpreted both by the Parlements at the time and by the bull of Pope Sixtus V) and also by the general consent of the French people (who, after all, made even Henri de Navarre finally accept the fact that he could not remain Protestant and be King of France).
Who then was the King of France between the Cardinal's death in 1590 and Henri IV's accession in 1593? And how could Henri de Navarre, if deemed passed over once in 1589, not be deemed passed over forever? I would think the true King in 1590-93 must have been Charles, comte de Soissons, the youngest son (and the only one likely to have been a Catholic) of the Cardinal de Bourbon's younger brother, Louis de Bourbon, Prince de Condé. Or, if the comte de Soissons and the rest of Condé's descendants were all Protestants in 1590 and therefore as ineligible as Henri de Navarre, and, if you think that anyone from an even more distant branch of the Bourbons too unlikely to be considered, then I'd say there simply was an interregnum in France (as there had been before Hugues Capet's accession). Moreover, if the comte de Soissons or anyone else in 1590-93 was the true king, the explanation as to how that true king suddenly stopped being king in 1593 once the re-Catholicized Henri de Navarre was universally accepted as king could be the same explanation as to how the last legitimate Merovingian and Carolingian kings stropped being kings when their successor dynasties took over the throne. And, in 1590-93 there certainly were in France and elsewhere plenty of rival families eager to claim the French throne through descent from Hugues Capet via one or more female lines. Henri de Navarre, however, trumped them all when he mooted the question of his ineligibilty by returning to Catholicism.
Whether someone, once passed over, can get back to the head of the line of succession at the next kingly vacancy by, in the meantime, having eliminated the cause of the first passing over is an interesting question. The nearest example I can think of is Romania (which also has the Salic Law and which in this century had a similar situation). When King Ferdinand I died in 1927, his son Carol was passed over in favor of his grandson Mihai because Carol was then living in adultery with Hélène Lupescu. Nonetheless. when three years later, Carol temprarily left Mrs. Lupescu, he was able to re-assume his dynastic rights and, with the consent of all, replaced the child King Mihai I and became King Carol II. He even claimed that his reign began in 1927, at the death of Ferdinanmd I. That Carol shortlyly afterwards resumed his liaison with Mde Lupescu is not really relevant. He got his rights back by having officially removed the cause of his having lost his rights in the first place. (Ten years later, Carol II was forced to abdicate, went off to exile in Mexico and Brazil, and later Portugal, with Mde Lupescu, and his son reigned once again as Mihai I.) The point of my raising all this is just to show that, in at least one case of a monarchy under the Salic Law, a prince's ineligibility in 1927 to be King did not affect his being considered once again eligible in 1930.
Keep up the good work.