alternatehistory.com

I was browsing the internet back in August and came across this interesting tidbit of info:

She [Anna Pavlovna] was considered to be a great match, and several candidates were turned down, including Napoleon, the Duke of Berry, the future Ferdinand I of Austria and the Duke of Clarence. In 1815 her brother chose the Prince of Orange, who had excelled as the hero of Waterloo. William traveled to St. Petersburg to meet Anna. Anna considered herself to be above him in birth, but the meeting went well anyway.

Apparently, Emperor Franz/Metternich broached the subject to Alexander during the Congress of Vienna (or shortly before). I realize the possibility of an Orthodox-Catholic match is awkward (although let's face it, three of the candidates considered were Catholic) I have a feeling that her brother would find a way to make it happen were he so inclined - what probably (IMHO) made him decide against it was due to his sister, Alexandra's treatment during her time at the Habsburg court.

But let's say for the sake of the WI the match goes through. I'm not ignoring the whole problems of the Catholic-Orthodox marriage @Valena & @alexmilman in the name of wishful thinking. However, I feel in 1815 the pope is going to be too worried about going back to Rome (and getting the Papal States back), so maybe Franz does a deal where the papacy gets Austrian support at Vienna (doesn't have to say how much support) in exchange for him granting a dispensation. And as said, if Alexander wants the marriage to happen, and the pope has granted the dispensation for the match to happen - Franz has probably also weighted it with the bride keeping her faith (her sister Alexandra was allowed to, so I'm not sure she wouldn't be) - can the Orthodox church still refuse to allow the wedding?
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