[quote=@Jig]
One or two decades works super-duper well. I'd've accommodated for longer ago, but, actually, if we can say for certain that it's one or two decades, that's absolutely ideal.

How belligerent would the Western territories of the Hungarian Federation have been: would they themselves have been aggressive, or been the victims of any aggression of mine?
[/quote]Up to you.
I did say that the League's strength was tested during the Great War so that means perhaps they were on the defensive at first.
I also assumed (though not wrote down) that the Italian and Swiss territories once belonged to whoever the nation in the center was, now taken by Franco-Iberia.