Imperial
When an army enters another nation's home province where a foreign army already sits, when is its hostile or friendly status declared, and who decides on a battle?
The rulebook does not fix the order; experienced players agree the status is declared on entry, before defenders decide on a battle.
The entering government declares hostile or friendly as the army enters, one unit at a time. The units already there then decide whether to call a battle, and the status does not change the fight decision.