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Steam News30 September 20259mo ago

Developer Diary | Doctrines

Hello! I am Jack, a recent Game Designer addition to the HoI IV team. I’ve been given the exciting privilege of presenting you with a feature/system rework: Doctrines.

In this update3

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Repeated intro

Hello! I am Jack, a recent Game Designer addition to the HoI IV team. I’ve been given the exciting privilege of presenting you with a feature/system rework: Doctrines.

What changed

1 fix3 additions4 changes0 removals
  • Compatibility
  • Maps
  • Gameplay
  • Fixes
  • Balance
changedDoctrines as a system has existed more or less untouched since the original release of the game, so when I was given the chance to rework and expand this system, I eagerly sank my teeth into it. Naturally, none of this could be possible without the most excellent help and input from my fellow designers; with very special thanks given to Zwirbaum (Tomasz), who has graciously listened to my questions and concerns, along with being a stalwart protector against frankly insane balance changes. Additionally, our beta testers have been a great help in preparing this.
changedThe intention of the Doctrine rework is to give players a more intentional gameplay experience when it comes to modifying and applying your armed forces. Instead of a single doctrine tree, we’re looking at something you build up and enhance over time by using your armies and equipment practically; namely, you should strive to put units in divisions, on the map, and use them in combat situations to actually upgrade their abilities. Free lunch is a figment of most of our imaginations, after all. Additionally, we want to give players more opportunities to play around and experiment with different division designs and their approaches to strategies in general.
addedLet’s get into the gritty of it! Behold, your new doctrine screen:
fixedThat does look a bit sad and empty, like a Swedish winter. Follow me along as we fill it up during this dev diary! (Not the winter. That’ll never be fixed)
addedGrand Doctrines & SubdoctrinesThe most obvious change for returning players will be the new Doctrine tab, along with a split, in what we’ve chosen to call Grand Doctrines and subdoctrines . The design and flavour intention of the split is basically to have a Grand Doctrine that encompasses your intention for the kind of warfare you wish to pursue, further supplemented by discrete improvements to units through the use of subdoctrines. Subdoctrines are the newer, more special part here, being tailored around choosing which units to enhance.
addedGrand Doctrines & SubdoctrinesIn the new hierarchy, if you’re not playing a nation that starts with a Grand Doctrine assigned, that is what you will select first.

Doctrines as a system has existed more or less untouched since the original release of the game, so when I was given the chance to rework and expand this system, I eagerly sank my teeth into it. Naturally, none of this could be possible without the most excellent help and input from my fellow designers; with very special thanks given to Zwirbaum (Tomasz), who has graciously listened to my questions and concerns, along with being a stalwart protector against frankly insane balance changes. Additionally, our beta testers have been a great help in preparing this.

The rework as presented still has some Work In Progress parts to it, so I would like to caution readers that things in here might still change to some degree by the time we release. A lot of changes and work have already gone into this, but it carries many small moving parts, with feedback constantly being factored in.

The intention of the Doctrine rework is to give players a more intentional gameplay experience when it comes to modifying and applying your armed forces. Instead of a single doctrine tree, we’re looking at something you build up and enhance over time by using your armies and equipment practically; namely, you should strive to put units in divisions, on the map, and use them in combat situations to actually upgrade their abilities. Free lunch is a figment of most of our imaginations, after all. Additionally, we want to give players more opportunities to play around and experiment with different division designs and their approaches to strategies in general.

Let’s get into the gritty of it! Behold, your new doctrine screen:

That does look a bit sad and empty, like a Swedish winter. Follow me along as we fill it up during this dev diary! (Not the winter. That’ll never be fixed)

Grand Doctrines & Subdoctrines

The most obvious change for returning players will be the new Doctrine tab, along with a split, in what we’ve chosen to call Grand Doctrines and subdoctrines. The design and flavour intention of the split is basically to have a Grand Doctrine that encompasses your intention for the kind of warfare you wish to pursue, further supplemented by discrete improvements to units through the use of subdoctrines. Subdoctrines are the newer, more special part here, being tailored around choosing which units to enhance.

In the new hierarchy, if you’re not playing a nation that starts with a Grand Doctrine assigned, that is what you will select first.

Ah, now it’s starting to look like something. Through picking our grand doctrine, we get a chance to see what Tracks we have available, to further customize our doctrinal interests.

Category Tracks

Subdoctrines are chosen by category, or Tracks. Each doctrine folder is associated with a set of tracks, in the case of Land Doctrines, these are “Infantry” “Combat Support & Artillery”, “Armor” & Operations. Rejoice, as you can choose one subdoctrine per track (and modders rejoice, the system supports an arbitrary amount of tracks). Assigning both grand doctrines and subdoctrines will cost you army xp, and some bonuses associated with the doctrines are unlocked immediately. You might however notice that not all bonuses are given at once. I mentioned that the doctrines build up and enhance over time, so how does that happen?

Mastery

Source

Steam News / 30 September 2025

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