Essential Hearts of Iron 4 Mods

By Edward Mass 13 Sep 2019 5

Of all the Paradox titles to deploy massive Mods libraries, none might compare with the whopping collection of over 20,000 Hearts of Iron IV Mods. Trying to pick and choose mods through this white-out of vast choices can be as daunting as Operation Barbarossa. Still, let's ride this tiger of selection and focus on four salient categories to encircle some of the best mods out there.


Modding has never been easier as the Steam Workshop literally makes adding a mod as easy as clicking the subscribe button on the mod's respective page. The mod will be automatically downloaded and will populate the mods section in HOI4's launcher. Here are some tips for first timers:

  • Check if the mod is up to date with the most recent patch for HOI4. Once a new expansion comes out you may have to wait a few days, weeks, or even months for bigger mods, until the mod is updated. Thankfully, HOI4 will give you a warning if you're about to load a mod that isn't up to date. Also, each mod will tell you on the side menu if it requires certain DLC.
  • Still want to play that favourite mod of yours but HOI4's latest update ruins your save game? You can always roll back your HOI4 version to continue your campaign. Check the mod pages on Steam or the Paradox forums on how to do this since it might be different for each mod and version of the game. If all else fails, ask in the comments threads for instructions!
  • Check if the mods you've selected are compatible with the other mods you've downloaded. This information is usually found on each mod's page as they usually list which mods they are able to run with.
  • Remember that most mods are not compatible with Ironman as they change game balance. If you're achievement hunting, you'll need to find those mods that will tell you in their descriptions that they're Ironman compatible.
  • Finally, sometimes it takes a while for the HOI4 interface to properly load the mod's latest version. Check if you have auto-updates enabled for mods and then, if you're unsure, simply relaunch the HOI4 launcher to check if all of the mods are present and up to date.

Keep in mind that not all mods might be found on the Steam Workshop even if the vast majority are. Simply check the Paradox forum for their listed mods and follow their instructions on their respective threads to download them. While the kinds of mods people want to look for is up to them, let's go through some key categories that will help catalyze that modding experience that has become such a staple for Paradox games.


Complete suites that tweak and alter everything about the base game. Mods such as these are some of the most beloved in any Paradox game and represent a whole new immersive experience.

BlackICE Historical Immersion Mod by Panzeroo and Team (Link)

One of the more famous mods from the days of Hearts of Iron 3, BlackICE is an immersion & realism mod aimed at making the game more challenging & historical. It's actually recommended that you play with 'Historical Focus' switched on for this mod, as it caters for the crowd who specifically want the challenge of WW2 as it unfolded, as opposed to the growing alt-history/sandbox crowd. Everything from new units and equipment, to new national Focus Trees (many borrowed from other mods that have done good work in this area), to expanding on the Law and Politics mechanics has been looked at. The AI is more challenging, there's more breadth and depth of options, and generally speaking this an excellent historical immersion experience.

BlackICE has been updated to be compatible with Man the Guns and the more recent 1.7.1 HYDRA patch.

Black Ice Hoi 4 mods

The Great War by Wolferos (Link)

Why fight WW2, when you can fight WW1 instead? The Great War does exactly what it says on the tin - Hearts of Iron 4 has been transformed to the world of 1910, where old-fashioned imperialistic powers jockey for supremacy at the dawn of the 20th Century. The game & mechanics have been completely overhauled to fit the period - that means that innovations like Tanks and Planes will take a while to enter the fray, so you'll mainly be looking at infantry tactics. The team is currently at work on bridging the gap between the First and Second World Wars, with work being done on the interwar tech and decision trees.

Fun fact, the developers of this mod have actually launched a Patreon to fund development of their from-scratch WW1 game, Fields of History: The Great War.

This mod is compatible with Version 1.7.1 & Man the Guns.

The Great War hoi 4 mods

The Road to 56 by Greatexperiment and Team (Link)

More than just extending the timeline to 1956, this mod peppers the entire world with greater detail and complexity. Not content to wait for Paradox to release content packs for various countries, The Road to 56 provides deep and sometimes quirky focus trees for dozens of countries overlooked by the base game. The most amazing part about this deeper focus on different countries is that it offers choices that go to the very heart of the focus system: the ability to choose a nation's destiny does not need to be an exercise in strict historicity. The creativity that the team places on the focus trees is bolstered by upgrades and expansions to the technologies, political mechanics, laws, etc. This is a one stop shop for a total enhancement of the game.

This mod is compatible with 1.7.1 & Man the Guns.

road to 56 hoi 4 mod

Hearts of Oak – Man the Guns by Hegemony and Team (Link)

Sometimes totally overhauling the game requires a subtle touch. In this case, Hearts of Oak does not attempt to change the base game into something unrecognizable but enhances and re-balances technologies, industries, wars, events etc. in areas where the Paradox team may have glossed over. Complete with a much improved AI, playing HOI4 no longer feels like a “solved” game as most playthroughs can be like but is a dynamic and challenging foray into the dangers of Global Total War. With a keen focus on deepening historical accuracy with challenges for the player, this mod succeeds in bringing more life to this cacophony of death.

This mod is compatible with 1.7.1 & Man the Guns.

hearts of oak hoi4 mod

Millennium Dawn: Modern Day Mod by Ted52 and Team (Link)

Winner of the “Outstanding Modding Achievement” at the 2018 PDXCon, this mod delivers exactly what one would imagine: the modern world set in stunning detail on the HOI4 Engine. This mod will be the closest we'll get to a global geopolitical grand strategy set in contemporary times and its fantastic depth makes it an exciting if not eerie look at today's world. One of the best examples of the impressive capabilities of totally overhauling the game, this mod promises political intrigue that's worthy of network news.

Update July 2019: Millenium Dawn appears to have run into a large amount of bugs due to the planned merging with other popular HoI4 mod, Modern Day 4, a short time ago. As of right this moment we can't 100% endorse the mod as it is very rough, but the quality of Millenium Dawn prior to the merge means that you should watch this space. We expect it to come back better than ever with MD4's outstanding depth thrown into the mix.

2 millenniumdawn


What's a World War II game without its fair share of 'What Ifs'? Perhaps no other period in history has entertained this question from historians and fans of history so here's a few mods that really take this inquiry seriously.

Kaiserreich by The Kaiserreich 4 Team (Link)

The veteran alternate history mod on the block. This mod can trace its origin back to Hearts of Iron II. Kaiserreich asks the daring question of: “What if Germany won WWI?”. A deeply rich world fourteen years in the making, every aspect of this alternate history is fully fleshed out in this latest incarnation to delight fans of the legacy of this mod as well as new players.

Tackling an entirely dynamic yet strangely parallel political landscape boasting thousands of unique events, fully fleshed out focus trees, and quirky interactions, this mod gives the player a tantalizing taste of living in an alternate timeline. A true joy to experience for the story and drama with brand new ideologies and situations based on all of the consequences of this “what if”. The visual appeal is impressive as the custom models and graphics add true immersion to this other world. If you're interested in learning more, we did a more in-depth analysis into what makes this mod so compelling.

This mod is compatible with Version 1.7.1 & Man the Guns.

kaiserreich hoi4 mod

Old World Blues by The OWB Team (Link)

Old World Blues brings the Fallout universe to HoI4, which makes for a surprisingly solid combination. The research tab has been replaced by a new tech tree, reflecting the state of the Fallout universe in 2275; some of the 'tribal' factions will be equipped with spears and scavenged firearms, where the more advanced factions can research and deploy the vaunted Power Armor that has been on the cover of most every Fallout release in the last few years. Many of the factions will have their own unique decisions and focus trees. Much of this will be familiar to players of New Vegas, but there is plenty grabbed from the lore of the first and second Fallout games as well.

There is a lot of depth here, and more on the way, as the modding team is looking to expand the map eastward past the plains and to the Atlantic coast, where we will see the Capital Wasteland and the Commonwealth of Boston represented as well. Keep your eye on this one.

Old World Blues is currently compatible with the most recent 1.7.1 update as well as Man the Guns.

hoi4 old world blues

World of Alternatives by GE (Link)

Alternative history doesn't need to be well thought out or meticulously storied. Instead, it can be a total chaos-fest. Enter the world of World of Alternatives, a mod which unleashes the limitations on AI choosing decisions that go against their historical probabilities. Now, Germans shall fight against Hitler, Russians won't be dying off in purges, and Japan becomes the leading force in the Comintern. The entire world becomes a roulette wheel of unpredictable outcomes which not only delights those looking for a definitely new playthrough but also showcases the rather amazing focus tree choices available that the player may have never known existed.

This mod is compatible with Version 1.7.1 & Man the Guns.

world of alternatives hoi4 mods

The Man in the High Castle by KryptoN (Link)

The disturbing counterfactual by Philip K. Dick turned popular modern television series comes to life in this mod which depicts the world in the throes of Axis hegemony and the tensions arising between the last two superpowers on the planet and their burgeoning dependencies. Thrilling in its premise, it is also a fun little scenario to play out. The choice is whether to complete the global takeover as one of the last major powers or to rise from the ashes of oppression and once again tilt the Axis of the world. Each nation is equipped with focus trees that reflect their present situation and the contextual support is fairly strong. Enjoyable even without knowledge of the fictional material, this mod is a showcase of taking the “what ifs” to a whole new level.

Update: The Man in the High Castle is currently on the backburner for the modding team, and is currently only compatible up to Version 1.5.4. It’s not certain whether development will continue, but it’s worth taking a look at if you’re into the world of this acclaimed TV show.

5 maninthehighcastle


Sometimes all you need is to get under the hood of that war machine in order to have a truly better experience than what the vanilla game can offer. Here are some mods that exemplify getting your hands dirty with blood and iron.

Expert AI 4.0 by Chondrite (Link)

This could also be considered an 'overhaul' mod of sorts given the extensive work done with the AI, but it's not meant to necessarily give the player an alternative scenario or a more immersive experience. Expert AI puts in a lot of behind the scenes work to make the AI a more challenging opponent for the players, specifically with the 1936 start with Historical Focus mode turned on. It's not able to address everything, but it touches a wide range of AI behaviours & decision making systems so that computer opponents fight smarter & harder. It's also not recommended you use this mod while playing minor nations.

This mod is compatible with version 1.7.1 & Man the Guns.

Expert AI 4 hoi 4 mods

Thicc Cities – Continued by Nunahur Al-Shamikh and Gojira (Link)

The amusingly accurate name delivers on its promise. Cities are now expanded into several provinces ramping up the siege drama of urban warfare. Single points and single army combat is expanded into a truly epic battlefield that does away with another layer of abstraction. A small change, but an incredibly rewarding one when such battles as Stalingrad and Moscow are finally more representative of their real history counterparts.

This mod is compatible with Version 1.7.1 & Man the Guns.

7 thicccities 

Player-Led Peace Conferences by Neutrino (Link)

Never to trust the AI to have our best interests at heart, it's time to take full control of the peace process through this mod. The obvious drawback is that this is not at all 'historically accurate' but it does offer the player the choice to roleplay their way into a more reasonable peace table if they so desire or just greedily skew everything in his or her favour. Simple yet this mod fixes one of the most annoying things about playing with AI allies.

This mod is compatible with Version 1.7.1 & Man the Guns.

8 player led peace

Operation Multiplayer by WASP (Link)

The combat-oriented focus of HOI4 makes it a popular destination for Multiplayer dueling between generalissimos. Thankfully, Operation Multiplayer exists to address some of the balance issues that would otherwise hamper a truly dynamic Multiplayer experience. This mod achieves a balance between presenting each player a chance to best the other while maintaining historical accuracy and immersion. After all, it's not enough to simply smash tanks together, but to do so in historical context is what makes this mod compelling. With a changelog so long, it's best to read all of the rebalancing on one's own to get a better idea of just how the multiplayer experience can be maximized through mods.

At the time of writing, the mod is only compatible with Version 1.6.x.

9 operationmultiplayer


Warfare never looked so good. Add some granularity to the epic warfare with these mods that truly highlight the hellish landscape of the most devastating war in history.

Soldier's Radio by The Soldier's Radio Team (Link)

While the epic tones of HOI4 may be great for the high stakes drama, it's still rewarding to sit back and listen to the music of the era and of the common soldier. Highly immersive and strangely sombre, this music pack of over 600 songs (though not all are historically accurate) aims to create a certain atmosphere that reminds the player that he's leading millions to death, heartache, and immortal glory.

With the addition of the new in-game radio, now is a better time than ever to try this mod out! Currently compatible with version 1.7.1.

soldiers radio hoi4 mod

HOI4 – Texture Overhaul – Terrain by Gorgulla (Link)

The nitty gritty of realistic global warfare is reflected in this meticulous reworking of the terrain textures into landscapes that not only look more realistic but speak of the startling scope of the conflict. A gorgeous tour de force, no one is the poorer for this graphical upgrade which brings an added level of immersion to the rampaging divisions vying for global control. One of the best things about this mod is that it does not sacrifice performance allowing the player to enjoy a greater expanse of visual goodies without any added lag.

This mod is only compatible up to Version 1.6.x, but it is compatible with Man the Guns.

9 c hoi4 texture terrain

Do you have any mod suggestions or personal favourites we can add to our list? Let us know in the comments!



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