Monaco succession crisis of 1918

The Monaco succession crisis of 1918 arose because France objected to the prospect of a German national inheriting the throne of the Principality of Monaco. Prince Albert I had only one legitimate child, the Hereditary Prince Louis, then heir apparent to the principality. As World War I drew to a close, Prince Louis, at the age of forty-eight, remained (legally) childless, unmarried, and unbetrothed.

Dynastic dilemma

Louis' nearest legitimate next of kin was Prince Albert I's first cousin Wilhelm, 2nd Duke of Urach (1864–1928). He was born in Monaco in 1864, and was largely raised there as a Francophone Roman Catholic by his mother after her widowhood in 1869. He was educated at the former Jesuit School until 1882. He was, however, a Württemberg national, and his adult domicile and main assets (including Lichtenstein Castle) were in Württemberg. Although he was awarded the Grand Cross of Monaco's Order of Saint-Charles and was a knight of the Sovereign Military Order of Malta, he also was awarded much later the Grand Cross of the Order of the Crown of Württemberg and was a knight of Kaiser Wilhelm II's Order of the Black Eagle. In 1871, Württemberg became a part of the German Empire. Wilhelm joined the Württemberg army in 1882, and by 1911 this coloured the status of his claim to Monaco.

His father Wilhelm, 1st Duke of Urach, had many connections to France before his marriage in 1863 to Princess Florestine. His first wife, Théodolinde de Beauharnais, was a grand-daughter of Empress Joséphine, Napoléon’s first wife. His cousin Catharina had married Jérôme Bonaparte, and their son Prince Napoléon Bonaparte was a senior adviser in the Second French Empire at the time of Princess Florestine’s marriage. Another cousin, Alexander, had married a daughter of Louis Philippe I in 1837. In turn, Wilhelm the 2nd Duke’s wife Duchess Amalie was descended through her mother from Louis XV. So there was no cultural or dynastic aspect in the von Urachs’ past that was anti-French, rather the opposite; but this meant nothing in the climate of ''Revanche'' between the French Third Republic and the new Imperial Germany.

The 2nd Duke, a descendant through a morganatic marriage of the royal family of Württemberg, was the elder son of Albert's aunt, Princess Florestine of Monaco. Although he was ineligible to inherit the crown of his patrilineal ancestors in Germany, given the line of succession to the Monegasque throne at that time, there was every likelihood that the principality would pass by lawful inheritance into Wilhelm's "German hands" upon the death of Prince Louis. However, given the bitter relations between France and Germany at that time – a socio-political legacy of the Franco-Prussian War of 1870–71 and then of World War I – France deemed it unacceptable for a country over which it had exercised ''de facto'' or ''de jure'' hegemony, intermittently since the 17th century and consistently for half a century, to fall into the hands of a German aristocrat.

Moreover, while the House of Grimaldi had close ties to France due not only to geographical proximity, but also to possession of estates (vaster by far than the territory of the principality) and financial investments there, nothing officially prevented the dynasty's political or cultural associations from focusing elsewhere. Moreover, the hereditary principle allocated monarchies according to one form or another of proximity of blood, and the Grimaldis' hitherto exclusive control of Monaco's dynastic marital policy was what threatened to enthrone a German duke on France's border, even after the Empire's defeat in war. Just as the ruling families of Britain, Russia, Belgium, and the Netherlands had all become patrilineally German by the twentieth century due to the propensity of monarchical heiresses, seeking dynastically equal marriages, to choose husbands from among Germany's many minor princely families, Monaco was on the verge of the same fate. Although the Grimaldis did not require inter-marriage with royalty by law as German dynasties typically did, by custom they never married subjects of their own realm, and no Monégasque reigning prince or heir had wed a French consort in more than a century.

By 1910, France also worried that Monaco might become a future U-boat base only 150 km from the important French naval base at Toulon. Louis had served in the French army for most of his life, and was a brigadier general by 1918. In contrast, Wilhelm had joined the XIII (Royal Württemberg) Corps in 1890, and had commanded the German 26th Division in 1914–17.

The "crisis" therefore hinged upon Monaco's legitimate order of succession