Simple enough WI...What if Charles of Austria had become King of Spain instead of Philip of Anjou?
Well, we would need another man to take over the Holy Roman Empire and a treaty assuring that Austria and Spain cannot be ruled by a single monarch...
But this could be done and if it could have, what would have happened during the course of the 18th century?
Spain can't be allied to Britain but they can't be allied to France, since there are no family ties between the royal houses of Spain and France...what would happen to geopolitics in Europe with this sort of Spain? a continuation of the 17th century?
Then there's the issue with Charles' issue...that is Maria Theresa of Austria, who would become Queen of Spain ITTL...or would she? would there be another war of the Spanish Succession over her taking over the reins of power in 1740 like it happened with Austria IOTL? there's no salic law in Spain, since it was brought by the House of Bourbon...but what would happen with her reign in any case?