Hearts of Iron 4 announced

The vanilla AI is pretty weak on the production side, though it has gotten better. If you want smarter production AI, you can use the Expert AI mod.

I guess I’ve played enough games that I know roughly what to expect. I do find it helpful to look on the details tab of the diplomatic menu to see estimates for divisions, aircraft count, mil factories, etc.

I think they will, but you can adjust how “brave” they are. If you want to keep them out of the fight, it might be better to move them further away from British bases (and have fighter on air superiority over the port, plus AA at the port).

I haven’t played Italy, but generally you want to fight your naval battles under “green air”. If you can get enough fighters on air superiority in the sea zone where you are fighting, their carriers will be largely neutralised ( I believe air superiority still suppresses CV aircraft?). If you can take out their fleet, supplying North Africa will be a lot easier.

If you find one, let me know! I feel this is one area where I was disappointed in the latest naval expansion. Everyone was begging for summarised results (especially for convoy raiding).

Do you mean that you are taking a lot of equipment losses that need to be replaced? Watch out for attrition, as that can get very expensive. You might take some attrition from heat in the desert but if you are taking a lot it is probably attacking into mountains or low supply. Low supply is very very bad.

Also, be careful about switching production around. Every factory you reassign takes quite some time to get back up to speed. If you’ve forgotten to produce some critical piece of equipment, sometimes it is unavoidable, but it is most efficient to evolve your production by adding new mils rather than switching a lot from one type to another. Though you do sometimes want to take the hit to start producing upgraded equipment.

Where do I find info about attrition? In the supply view? Looks like all of my armies are supplied, so it may have been environmental factors in Ethiopia and Albania.

Looking at it more now, I think I overproduced my infantry. In August 1939, I have 72 20-width infantry plus a dozen garrison and motorized divisions each. Of those, about 55 divisions are engaged. With 12 factories I’m outputting 80 rifles / day and consuming 200 in reinforcements.

If your divisions are suffering attrition, they will have a skull symbol - if you hover over that it shows sources of attrition and what the rate of equipment loss might be for the various types of equipment you have.

Another thing you can do it look at your land theatre. There is a scroll-like button that if you open it shows tabs for battles won, etc. Look at the equipment tab and you can see equipment losses in the last N months from combat and attrition (and how much combat losses you’ve inflicted on the enemy).

Do you have an infantry equipment shortage? Perhaps you just deployed more divisions that you could equip. Or you’ve lost a lot of equipment to attrition or combat. Unlike previous versions, just having divisions sitting around doesn’t consume industrial output.

If you have big equipment shortages, it might be better to merge some divisions rather than have a bunch of partially-equipped divisions. Two half-strength divisions fight much worse than one full-strength division.

Edit: Another thing that can inflict a lot of equipment losses is having a few transports sunk while moving a division across the Med.

Edit2: Actually 55 divisions engaged in constant combat would be a big drain on equipment just by itself, so I guess there is no surprise there.

France 2.0.

The details in the diary make playing France sound really fun to me. A lot of issues to manage and carefully balance, all the while Germany looming over you.

I’m really interested in the potential changes to occupation and resistance mechanics coming next week. One of the issues in the game is that occupation is pretty profitable in terms of industry and not very difficult to keep resistance down.

Agreed! I’m getting pretty exciting for this expansion already. With the USSR already being ruled out (they’ll get their own expansion to themselves, when the time comes) my hopes of a Mediterranean expansion might be coming true. I’ve really been pining for (new or overhauled) Focus trees for:

  • Italy
  • France
  • Spain
  • Greece
  • Turkey

Italy has been one of my favorites to play and while they had one of the better vanilla trees, it’s showing its age. I kind of felt the same way about France. While Spain wasn’t in the war, the Civil War is in-game and is important in the pre-war period. Given that the dev team shifted to allow more alt-history options, I’d love to see a focus tree for them. Greece deserves one and Turkey is in such an interesting place strategically, they could be a fun “what if” minor.

The promised rework of occupation mechanics:


These seem like good concepts. I’m interested to see more detail like the effects of laws, but they probably don’t have solid numbers yet.

I particularly like this part:

Colony states will be removed as a concept and every state not controlled by a nation with a core on the state will be viewed as occupied. Occupied states will now be less rewarding for the occupier. Access to the factories and resources of the state will by default be much lower than before. However, the conqueror can get more out of the state by cultivating compliance or adjusting occupation laws. This gives a bit of granularity between what was previously colony states and cores.

This removes the “hey, I signed a peace deal, so resistance is totally gone now” effect. Though it would still seem a bit cheap if you can set up a puppet that has no resistance due to having cores on everything. Maybe puppets should have a mechanic gaining cores?

Oh I really like this mechanic. It seems like it is gone to impact both German gobbling up territory pre-war as well as making France and Britain devote some resource to garrisoning their colonies.

There is also talk that garrison divisions may not be required to be on-map. Not sure how that would work, but anything that reduces division spam and map clutter sounds good.

I have mixed feeling about that, and seems to be conjecture at this point. On one hand dealing with garrison is tedious and no fun. On the other hand on my more than few occasion my garrison units have held the line long enough for me to send reinforcements against invasion or even my Polish garrison against a Russian counter offensive. So I tend to have 2nd line garrison troops with support artillery and engineering and 5-9 battalion and Equipment 1 for place like French coast and Norway, and pure cavalry units for the Balkans

This seems very historic. What isn’t historic is having cavalry count as double, or MP companies being yet another thing you have to research and pretty underwhelming.

Is it historic though? I genuinely don’t know as it’s not an area I’ve personally researched all that much - are there many instances of garrison units proving key to the defence of an area?

I guess another question is there a difference between bespoke garrison units, and front-line/combat units that are taking a rotation to do some ‘lighter’ garrison work?

I believe so. If you think of the of folks manning the Atlantic wall, there were mainly old men, wounded, and foreign conscript soldiers from occupied countries (Poles, Russians etc.). They did pretty good job in defending on D-Day until the real Wehrmacht army arrived. There were also plenty of German units that were rotated to the west to rebuild after they had been badly mauled in combat, again they were present in both D-Day and Anzio

Finally, SS garrison units with MP companies (i.e. Gestapo ) were pressed into combat many times as last ditch defense against advancing Russian. I don’t’ think most were particularly effective, but other than reading the Final Days, decades ago, I’m no expert.

Thanks. I spent my first three games overextending my production, first by not manufacturing enough equipment and then by training too many units. I suppose it doesn’t need to be said again, but this is an awesome production system.

Does anyone have tips on names and icons for divisions, armies, groups, theaters, etc.? I’m using codes for divisions (e.g. Infantry 20-7i.2a-ER), but I haven’t figured out a system for identifying armies or task forces yet.

I’ve definitely got better after 1000 hour of figuring out how to balance those. But, I can say the day I play game where I don’t have a shortage or a massive surplus of something, will be a miracle.

When I’m on the offensive, I use the destination of the army. So Minsk, or Moscow, or Suez Assault (my artillery heavy infantry) army. When I’m on the defense aka Russia I never did come up with a good system.

Dev diary discussing Free France / Vichy France in the next expansion.


This is when I feel sorry for a game designer:

Vichy France is perhaps the best example for what I like to call “trying to fit a history-shaped peg through a mechanics-shaped hole”. They were a puppet state of Germany by any reasonable metric - except they never formally joined the war. They weren’t at war with the Allies - and yet there were several battles between Allied and Vichy forces in Syria, Madagascar and most famously Dakar and during Operation Torch. Even after the battles were fought, however, Vichy France did not join the war, and the Vichy French troops engaged there were usually repatriated by the Allies after operations were over.

Still, the DD doesn’t make clear at all how the Allies do something like Torch without going to war with Vichy France.

I think this mechanism on how you can do this. But I’m not exactly sure what that means.

Option two is to intervene militarily, in areas that you have access too. This takes the form of the border wars, allowing you (or, more likely, your allies) to take over territories from Vichy France without going into a full-blown war. Not all areas can be taken over by border wars - Madagascar doesn’t border any other state from which an intervention could be launched, so you’ll have to find a different way.

I can see them using the border-war mechanic in some places. I’ve never actually had a border war amount to anything, but it is at least a sort of undeclared war.

I don’t know how that works for a naval invasion like Torch though, and they specifically seem to rule out “border war through naval invasion” in the case of Madagascar. I guess they have something up their sleeve.

I liked this comment from the forum.

These changes look awesome!

Also great to see (as a dev myself) that things aren’t cobbled together with tape ;)

All be impressed if they can pull off their objectives in a way that the AI can understand.