Bit of a necro post here, but I figured I'd add my $0.02, having done this last night.
I followed the steps outlined (mostly) by Parallel Pain, and found them to be pretty successful. There were basically two phases of the war, one involving vassalizing Scotland, and the other involving taking out France. I got lucky, in that I managed to secure alliances with multiple larger nations, and brought Austria in to the war against the French. My basic steps were as follows:
Day 1:
- Followed Parallel Pain's guide to the letter.
Then:
Diplomacy:
-General tip: Set the timer to 1, and make sure that the return of ambassadors is a "pop up and pause" event. You'll need to manage this stuff relatively quickly and get the ambassadors moving around frequently. Don't sweat screwing your diplomacy points. You can reverse that when Henry dies and you won't be flipping province cultures at this point.
- Try to secure alliances with Austria and Castille as soon as possible. I did this by securing royal marriages with them, then alliances. I couldn't do an alliance right out of the gate.
- AFTER declaring war on Scotland, call Portugal in to the war. If you can get Austria or Castille to join you, do that.
- Additional assistance: It can be helpful to get military and fleet access to Navarre and Brittany, as well as military access to Castille. You MAY need to beat a hasty retreat. If so, you'll want to be able to land your ships in their ports as well as retreat your troops. I'll explain why naval access is helpful below.
- After you PU France, my advice is to start improving relations with them. This will help maintain the PU after Henry VI dies.
- To the extent it's possible, try to both improve your relations with the Papal State, and play the Cardinal game to get more cardinals on your side. If you can become Papal Controller, it'll help, but it's not absolutely essential.
Warfare:
- I mostly followed Parallel Pain's guide.
- Generally: The goal here is to exhaust France's manpower. They have considerably more than England, but particularly if you can pick off smaller siege armies quickly with Richard Plantagenet's 8/6 stack, France will soon find itself having to replace multiple regiments or go without. This is also where Allies can really really help. Even if they get defeated, they're still bleeding France dry of men. Portugal will help you in that regard, but either Austria or Castille (or hey, both, if you're lucky) will really help, since they can each bring the pain. Once France is sufficiently bled out, you simply place siege stacks on as many provinces as possible (and for this, I'd hit Barrois, Maine, Anjou, and Provence itself, then force it to release provinces to France -- which you'll then have to siege again), blockade as many ports as possible, and try to get yourself as high a war score as possible in as short a time as possible. You want to avoid war weariness, and knowing England at this point, you'll get plenty of annoying "comets sighted" and other stability-decreasing events or revolts, so you want to wrap it up quickly and nab the PU.
- Protip: Ok, so this may be more of a "newbie" tip, but it was something that I didn't know, even as an EU3 player (although not a very good one). It is faster to land transports to load and unload troops than it is to do "amphibious assaults" so to speak. Obviously, you can't do this on enemy territory, but you can do it on friendly territory or land where you have military and naval access. This is where naval access to Navarre and Brittany comes in handy. If, by chance, you need to haul ass out of your territories in France, and you can't get to your own provinces in time, you may be able to play for time by landing a ship in nearby territory, getting your troops there, and attaching them to the transport. Then you simply sail off (although watch out, it can sometimes take a second to successfully load everyone), and leave the French shaking their fists in impotent rage on the shoreline while you jeer.
- I used Richard Plantagenet's single 8/6 stack to siege Bearn, then left him there for a bit, to see if it would draw French forces south. The French gradually split up their mega stacks, and my Austrian allies whittled several of those down. Eventually they were low enough and with low enough morale that I could sic Richard on them, and he usually took them out before whatever larger army there was about was able to attack.
- Meanwhile, with the main French army occupied in the south, I sent Henry Percy to siege Ils-de-France. Taking that gets you around 30 warscore, which means you're almost halfway to you goal.
- It's feasible to blockade the French ports, too, since they only have three -- one in Poitou, which happens to be in the same sea zone as your Gascony/Labourd provinces, and I think two in the Mediterranean. This will mean, however, that you need to keep your naval maintenance up, but hopefully you can do this after taking over a few French provinces.
I did all this by around 1451-ish, never hired more troops, and secured a personal union with some extra cash. Couldn't get enough WS to steer trade, I think, but I'd have to check. After that, I started improving relations with an eye towards eventual integration.