The Bonapartist Claimants
The "Law of Succession" Napoleon I established on becoming Emperor in 1804 provided that the Bonapartist claim to the throne should pass firstly to Napoleon's own legitimate male descendants through the male line. At that time he had no legitimate sons, and it seemed unlikely he would have any due to the age of his wife Joséphine. His eventual response was the unacceptable one, in Catholic eyes, of engineering a dubious annulment, without Papal approval, of his marriage to Josephine and undertaking a second marriage to the younger Marie Louise, with whom he had one son. The law of succession provided that if Napoleon's own direct line died out, the claim passed first to his older brother Joseph and his legitimate male descendants through the male line, then to his younger brother Louis and his legitimate male descendants through the male line. His other brothers, Lucien and Jerome, and their descendants, were omitted from the succession (even though Lucien was older than Louis) because they had either politically opposed the Emperor or made marriages of which he disapproved. By Marie Louise Napoleon had one son, in whose favour he abdicated after his final defeat in 1815. Although the Bonapartes were now deposed and the old Bourbon monarchy restored, Bonapartists recognized this child as Napoleon II. However, he was sickly, virtually imprisoned in Austria, and died young and unmarried, without leaving any further direct descendants of Napoleon I. When the Bonaparte Empire was restored to power in France in 1852, the Emperor was Napoleon III, Louis Bonaparte's only living legitimate son (Joseph having died in 1844 without ever having had a legitimate son, only daughters).
In 1852, Napoleon III, having restored the Bonapartes to power in France, enacted a new decree on the succession. The claim first went to his own male legitimate descendants in the male line (though at that time he had none; he would later have one legitimate son, Eugène Bonaparte, who would be recognized by Bonapartists as "Napoleon IV" before dying young and unmarried). If his own line died out, the new decree allowed the claim to pass to Jerome, Napoleon's youngest brother who had previously been excluded, and his male descendants by Princess Catharina of Württemberg in the male line (but not his descendants by his original marriage to the American commoner Elizabeth Patterson, which Napoleon I had greatly disapproved). The only remaining Bonapartist claimants since 1879, and today, have been the descendants of Jerome and Catherine of Württemberg in the male line.
In their willingness to ignore primogeniture (the exclusion of Lucien Bonaparte and his descendants) and their cavalier approach to the Catholic belief in the indissolubility of marriage and to the Pope's rights as final arbiter on the validity of marriages, the Bonapartist laws of succession were far from traditional; but then, the whole claim of the Bonaparte family to rule France was far from traditional.
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