Diplomacy
Does setting the campign difficulty to very hard make the AI players irrationally reluctant to accept peace with the player, playing as France? During the period, Napoleon used the tried and tested theory of "After the war is over, make alliances", hence why there were Saxon, Austrian, and Prussian troops in the Grande Armée that marched on Moscow. At the moment, however, the only way I've managed to make peace with one member of the coalition is by capturing Vienna as part of the mission. For the record, Austria re-declared war on me about 4 turns later after refusing to even countenance an alliance, despite offers of returning Vienna to them.
I recently wiped out the entirety of Prussia's armies in a battle that took 45 minutes and saw me withdraw one and a half shattered armies so that fresh reinforcements could make it onto the field. Is Prussia ready to accept peace now? Not on your life, not even after I sacked Berlin.
I realise this is a bit of a rant post rather than offering anything constructive but has anyone managed to have effective diplomatic manoeuvering? Do I need to office a substantial cash bribe or soften them up with state gifts first? While I love the innovation of liberating nations and establishing protectorates just as Napoleon did, the lack of forced alliances with beaten Coalition members is rather depressing. Furthermore, I was under the impression that your protectorates were meant to obey you diplomatically and yet I can't get a single one to declare either a trade embargo or break off alliances that they may have. Diplomacy was, I daresay, somewhat better in ETW when you could get a very favourable peace after taking an important town from another nation.