What if the Dutch decided that they didn't want to take over the Austrian Netherlands and Luxembourg in 1815?
If that is plausible, what becomes of the Austrian Netherlands and Luxembourg? Do they remain under the Hapsburgs by default? The only other options I can think of are that Belgium and Luxembourg are set up as independent states sooner or Prussia takes them over in 1815. Are there any other possibilities?
If they do remain Hapsburg territory by default, would they be part of the German Confederation? I think they would because the Austrian Netherlands and Luxembourg were part of the Holy Roman Empire so is it likely that they would both be part of the German Confederation. Would it alter German politics in the period 1815-66 significantly if they were part of the German Confederation?
Assuming that the Austro-Prussian War of 1866 still happens and Prussia still wins, what becomes of the Austrian Netherlands? My guess is that the Kingdom of Belgium is created 1866 and Prussia annexes Luxembourg. Germany still looses World War One and Luxembourg is annexed by Belgium in 1919.