After the death of [Friedrich Wilhelm, Duke of Schleswig-Holstein-Sonderburg-Glücksburg](https://en.wikipedia.org/wiki/Friedrich_Wilhelm,_Duke_of_Schleswig-Holstein-Sonderburg-Gl%C3%BCcksburg) in 1831, his eldest son, [Karl](https://en.wikipedia.org/wiki/Karl,_Duke_of_Schleswig-Holstein-Sonderburg-Gl%C3%BCcksburg), succeeded him, but his younger children grew up in the Danish royal court. In addition to also descending from [Frederick V of Denmark](https://en.wikipedia.org/wiki/Frederick_V_of_Denmark) and [Louise of Great Britain](https://en.wikipedia.org/wiki/Louise_of_Great_Britain), fourth son [Prince Christian](https://en.wikipedia.org/wiki/Christian_IX_of_Denmark) (IX), then 12, was a nephew and godson of [Frederick VI](https://en.wikipedia.org/wiki/Frederick_VI_of_Denmark), whose wife, [Marie of Hesse-Kassel](https://en.wikipedia.org/wiki/Marie_of_Hesse-Kassel), was the elder sister of Friedrich Wilhelm’s wife, [Princess Louise Caroline of Hesse-Kassel](https://en.wikipedia.org/wiki/Princess_Louise_Caroline_of_Hesse-Kassel).
Because Denmark practiced Salic (agnatic) primogeniture, when Frederik VI died without sons in 1839, the throne passed to his heir presumptive, [Christian VIII](https://en.wikipedia.org/wiki/Christian_VIII_of_Denmark) (53), elder son of Frederik VI’s late younger half-brother [Hereditary Prince Frederick](https://en.wikipedia.org/wiki/Frederick,_Hereditary_Prince_of_Denmark). Christian VIII had been married twice and only produced one child, future [Frederick VII](https://en.wikipedia.org/wiki/Frederick_VII_of_Denmark) (30), with his first wife, [Charlotte Frederica of Mecklenburg-Schwerin](https://en.wikipedia.org/wiki/Charlotte_Frederica_of_Mecklenburg-Schwerin), early in their marriage. Two years prior, Crown Prince Frederik had divorced his first wife, [Vilhelmine Marie of Denmark](https://en.wikipedia.org/wiki/Vilhelmine_Marie_of_Denmark), Frederik VI’s younger daughter, and not sired a child with her during their 9-year marriage, nor with any of his many mistresses and flings since adolescence. Second to the throne was Christian VIII’s younger brother, [Hereditary Prince Frederick Ferdinand](https://en.wikipedia.org/wiki/Ferdinand,_Hereditary_Prince_of_Denmark) (47), who hadn’t sired any children with his wife, [Caroline, Hereditary Princess of Denmark](https://en.wikipedia.org/wiki/Princess_Caroline_of_Denmark) (46), Frederik VI’s elder daughter.
In 1839, Princess Wilhelmine Marie had been married to Duke Karl of Glücksburg for over a year and still wasn’t pregnant. The royal family *must* have suspected the male line of the House of Oldenburg was facing imminent extinction; yet the new king, an absolute monarch, did nothing to immediately rectify the impending succession crises.
In 1846. still childless CP Frederik divorced his second wife, [Caroline Mariane of Mecklenburg-Strelitz](https://en.wikipedia.org/wiki/Caroline_Mariane_of_Mecklenburg-Strelitz) , paternal first cousin of Dowager Duchess Louise Caroline, whose ten children were childless except [Friedrich](https://en.wikipedia.org/wiki/Friedrich,_Duke_of_Schleswig-Holstein-Sonderburg-Gl%C3%BCcksburg), who (then) had only one daughter with [Adelheid of Schaumburg-Lippe](https://en.wikipedia.org/wiki/Princess_Adelheid_of_Schaumburg-Lippe), and Christian, who already had two sons and a daughter with double cousin [Louise of Hesse-Kassel](https://en.wikipedia.org/wiki/Louise_of_Hesse-Kassel) *in only 4 years*. Wilhelmine Marie still hadn’t had any children with Karl of Glücksburg either. By this point, the longevity of the female line of royal Oldenburg was looking doomed as well.
Christian VIII still didn’t promptly address the succession.
In mid-1847, when his health was failing and Ferdinand was looking a little tire, Christian VIII decreed a change to the succession law from Salic agnatic to Semi-Salic male-preference so that the throne would pass to their pro-Danish sisters, childless [Juliane Sophie](https://en.wikipedia.org/wiki/Princess_Juliane_Sophie_of_Denmark) and fertile [Louise Charlotte](https://en.wikipedia.org/wiki/Princess_Charlotte_of_Denmark) and her children, including the aforementioned Louise, by proximity of blood, rather than passing to the pro-German senior cadet branch and line descending from Frederick VI’s only sibling, [Louise Auguste, Duchess of Augustenburg](https://en.wikipedia.org/wiki/Princess_Louise_Augusta_of_Denmark), who almost certainly was not the biological daughter of mentally handicapped [Christian VII](https://en.wikipedia.org/wiki/Christian_VII_of_Denmark). This Hail Mary play was the root cause of both Schleswig Wars.
But what if Frederik VI legally adopted his fourth nephew Christian before he died? Or Christian VIII had adopted him and made him a Hereditary Prince during his reign? Would an adopted Oldenburg have satisfied the duchies’ inheritance stipulations?
Would Frederik VI’s “son” CP Christian have trumped heir presumptive half-cousin Christian? Would he become King Christian VIII rather than XI, perhaps with his half-uncle regent during his minority?
Would Christian VIII’s “son” HP Christian have trumped his brother HP Ferdinand as Frederik VII’s heir, thereby negating the need to change the succession laws and punting the Schleswig-Holstein Question indefinitely?
If Christian were CP in 1837 when Victoria inherited the British throne, he would have been the future monarch of another country and dismissed like Tsesarevich Alexander (II) was–although Denmark was barely a Power much less a Great Power like Russia was.
However, if Christian VIII (or Ferdinand) had adopted him before William IV died as a backup because the dynasty was getting a bit thin, Christian would have been third (or fourth) from the Danish throne, which wouldn’t have automatically disqualified him as a potential Prince Consort for his year-younger third cousin. Victoria did like Christian when they met at her coronation. William IV loathed the Saxe-Coburgs and thought Albert was sickly (which he was). If he’d arranged a marriage for his niece and heiress presumptive before he died, then the Duchess of Kent and her brother, Leopold of Belgium, wouldn’t have as much power to push her toward their nephew. Not saying Victoria wasn’t attracted to Albert, but she wouldn’t have much of choice if she were already betrothed… or she could have picked Christian herself since as HP he wouldn’t be a country bumpkin. Bonus for her if she had, since he outlived her and obviously had healthy swimmers too.
Would he still succeed Frederick VII if he were PC of the UK? Would Victoria then become Queen Consort of Denmark? Would Prussia/Germany still have tried to annex the duchies if Britain was firmly involved? Who they have agreed to separate them so the personal union between the Danish Crown and Holstein and Saxxe-Lauenberg could be dissolved and Schleswig could be reintegrated with Denmark?
by PlicketyCat