There is an article (archive) on the Anjouist/pseudo-legitimist site known as Vive le Roy. Naturally, they support the wrongful King of France, Don Luis Alfonso Gonzalo Víctor Manuel Marco de Borbón y Martínez-Bordiú, whom his supporters call “Louis XX.”
[It is worth noting that despite our opposition to Don Luis’s pretentions to the French Throne, we hold nothing against him and agree with many of his political views. We most certainly agree with his continued support of the legacy of his grandfather, Francisco Franco, who saved Spain from republicanism and communism. And we certainly hope that Don Luis succeeds to the Duchy of Franco.]
The article explains the origins of the controversy between the elder Bourbons (the Spanish Bourbons) and the junior branch, the Orleans, while also defending the claims of the former.
One of the best lines from the article is as follows:
Few in number, the Whites of Spain attempted a propaganda effort. They needed to have a press, since most of the old Legitimist newspapers had gone to Orléans.
One wonders why the old Legitimist newspapers went to the Orleans. Perhaps because they Spanish Bourbons were foreigners and incapable of being the Kings of France? Perhaps, like the French of old, they did not want foreigners on the throne.
Then there is this:
As for the Lemaistre judgment, when it mentions that a “ foreigner“Cannot surround the crown of France, it is certainly targeting the Infanta Claire-Isabelle, candidate of the King of Spain, or the Duke of Savoy, but also princes accustomed to France who, although of Lorraine origin, could pass for French such as the Guise. It is, in a way, the claim of the right of blood against the right of the soil: the Lemaistre judgment considers as dynasts in France the princes of Capetian blood
The author’s justification for this is found in footnote 33:
We could give the example of Henri IV, who was king of Navarre in the second generation, therefore a foreign king. While the leaguers wanted to prevent him from acceding to the throne, they put forward his Protestant religion, but never his nationality. If the rule had been different, the opponents of this king whom they considered undesirable would have used it to remove him.
Henri was certainly King of Navarre, but was not a foreigner. Born in the state of Bearn in December of 1553, he was a natural Frenchman because the Parlement de Paris ruled in 1505 that the Bearnais were natural Frenchmen. This was confirmed again in 1579.
Also being the king of a foreign state or owning foreign possessions did not make one a foreigner. Francois II was the King Consort of Scotland, but no one considered him a foreigner. Many other French kings had foreign possessions. Navarre had previously been in personal union with France before severing due different succession laws.
Now, let us discuss Infanta Isabella Clara Eugenia (supported by the Catholic League). The main objections to her was not that she was a woman, but because she was a foreigner. It should be noted that her being a woman made her invalid a priori because of the Salic law denying the throne to women.
In response to the Infanta’s claim, the French replied:
…our laws and customs prevent us from calling forward as king any prince not of our nation.1.
Further the jurist Pierre de Belloy, a supporter of Henri IV, explains the purpose of the Salic law and denying the throne to women and the decedents of the daughters of France.
Now it is quite certain that, without a Salic law, the Crown would have been exploited by an infinite number of non-French Princes [Princes non François], by the marriages of my daughters, daughters of France, who are married in a foreign nation, often in England, Spain, in Germany, in Lorraine, in other provinces of Europe…
- David Buisseret. P. 43 Henry IV: King of France.
The French Unionist Project 