As I understand it, the answer is no but would love the move official people to weigh in.
I suspect that the rule as I understand it is a bit cleaner:If a germany falls falls (say to UK) then all territory belonging to Germany stays German. Suppose, all while Berlin is UK hands, US takes France ––> US gets France. If next, Japan takes France, then Japan gets to claim France. If next, Berlin is liberated, then France immediately goes back to Germany.
And, for factories, I think the rule is:A country can only use an IC in a territory that they controlled at the beginning of their turn.
Some please correct me if I’m not getting the rule right.
All above is correct.
What about when german units are available in a german country and Japanese units move in. Does Japan get to claim it or is it only when no German units are there?
In order for Japan to conquer (versus liberate) a German controlled territory after Berlin has fallen, the territory has to be taken by an allied power. Just moving Japanese units into a Germany territory does nothing to the ownership of the territory, whether Berlin was lost or not.