(Yes, yes, I know theres the other Spanish Succession War TL, the Royal Knockout, and Im actualyl wirting on the first article atm [as nobody else seems to have any remaininbg interest in it, it seems Ive de facto usurped it], but well, for a quick WI... of course, there will be many similarities)
IOTL, France won - not decisively (hence allowing for TLs like French Victory at Blenheim), but it did win the main price, Spain and her colonies, as a secondogeniture. For soem reason, total French victory has been far more dealt with than the opposite, so here it is:
What if the Alliance wins?
This would install the Archduke Charles as Emperor. IOTL, Charles became Holy Roman Emperor when his brother died without male heir, but ITTL, this is impossible - the Sea Powers and France will throw a hissy fit about th eprospect of uniting the two realms.
Hence, Emperor Joseph's daughter Maria Josepha will succeed him IOTL in Austria, who is married to August III of Saxony-Poland. Hence, we would see an Austria-Bohemia-Hungary-Saxony-Poland-Lithuania union
Whereas in Spain, the younger line Habsburg-Spain will also die out in the male line after its first king, as of course Charles had no sons, either, only daughters - one of them being Maria Theresia, IOTL Austrian Monarch and Holy Roman Empress (consort). Assuming shell marry as IOTL, well see Houses Habsburg and Lorraien fusing as IOTL.
Which leads to the total reversal of the IOTL situation - Habsburg (well, a House that calls itself Habsburg, or Habsburg-Lorraine to be exact) continues to rule in Spain, but not in Austria. Whereas in Austria, we have aforementioned super-personal union...
Thoughts?
