Developer diaries

Hearts of Iron IV

Version history

Man the Guns

1.6 • 1.6.1

Waking the Tiger

1.5 • 1.5.1 • 1.5.2 • 1.5.3 • 1.5.4

Death or Dishonor

1.4 • 1.4.1 • 1.4.2

Together for Victory

1.3 • 1.3.1 • 1.3.2 • 1.3.3

Base version

1.2 • 1.2.1

1.1

1.0 • 1.0.1

Developer diaries are articles, sometimes accompanied by videos, published by Paradox to describe the game design in detail.

Unannounced Content

All developer diaries about patch 1.7 (aka Hydra) and unannounced content for patch 1.8 (aka Husky).

No.	Title and Link	Description	Date
1	News from the Eastern Front	Patch 1.7 'Hydra' bringing 64 bit, AI frontline & player frontline UI changes	2019-05-08

Man the Guns

All developer diaries about the Man the Guns expansion and patch 1.6 (aka Ironclad).

No.	Title and Link	Description	Date
1	Man the Guns and PdxCon	General goals for the future expansion and patch	2018-05-23
2	Fuel	Information on fuel and new hotfix.	2018-06-27
3	God Save The King: British Focus Tree Rework	Reworked British focus tree, allowing for alternate-history paths.	2018-07-04
4	A Post-Colonial World:Map Changes and New Tags	Sweeping changes to the map along with the addition of more releasable tags.	2018-07-11
5	Custom Gameplay Rules	New Custom Gameplay Rules allowing the player to steer the game in the direction they want.	2018-08-01
6	MTG - Bag of Tricks	Smaller improvements to the game such as assuming leadership of a faction, manual focus cancellation, and naval and air exercises.	2018-08-08
7	Naval Access	Improvements to the naval theater of HOI4 including marking dangerous seazones and asking for naval access to ports.	2018-08-15
8	Mines and Minesweeping	Naval Mines added to the game along with minesweeping.	2018-08-22
9	USA focus tree rework	Reworked USA focus tree, allowing for alternate-history paths.	2018-08-29
10	Modding and Traits	Added trait system for admirals as well as more features for modders.	2018-09-05
11	Naval Production, Repair and Damage	Extensive changes to the naval theater with reworks of ship production, repair and damage.	2018-09-12
12	Exiled Government	Extend possibilities for exiled governments and more information about the British focus tree overhaul.	2018-09-19
13	Je Maintiendrai	Announcement of and information about the new Dutch focus tree.	2018-09-26
14	Amphibious Vehicles and Research	New Amphibious Tractors and Amphibious Tank.	2018-10-03
15	Naval Terrain	Overview of new terrain types for seas.	2018-10-10
16	Naval changes #1	Overview of the different changes to naval warfare.	2018-10-17
17	Mexico focus tree	Announcement of and information about the new Mexican focus tree.	2018-10-24
18	Bag of Tricks 2	Expeditionary Force Requests, Supervised States & On-map decisions.	2018-10-31
19	Ship Designer	Overview on modifications on the ship designer system.	2018-11-07
20	Naval Treaties and Ship Refits	Naval treaties effects on ship designing and refitting of obsolete ships	2018-11-14
21	Naval Rework #1	New mission types and changes to the naval interface	2018-11-21
22	Bag of Tricks #3	Dutch & British focus changes, ideology drift tweaks, map changes in Africa and the Balkans region.	2018-11-28
23	New Naval Combat	Rework of naval combat to be more informative and less decisive	2018-12-06
24	Subs and Convoy Raiding	Improvements to submarine convoy raiding	2018-12-12
25	Fuel Review and Motorized Artillery	Changes to the fuel implementation and the addition of motorized artillery units	2019-01-09
26	Tech Changes	Changes to the tech research system and the addition of new naval techs.	2019-01-16
27	Art and Music	New music, 3D models and 2D art to ramp up MTG's awesomeness.	2019-01-23
28	The Imperial Japanese Navy	An AAR of Archangel85's experience with the Imperial Japanese Navy in a MP session.	2019-01-30
29	Achievements	New goals to strive for, with the addition of 21 new achievements related to MTG.	2019-02-06
30	AI Plans	More AI strategy plans, and the integration of AI strategy into the Custom Game Rules menu.	2019-02-13
31	Man the Guns MEGA RECAP	Recap of everything that has been announced.	2019-02-20
32	HOI4 Dev Diary - 1.6 Patchlog	Full 1.6 "Ironclad" patch log and Reddit AMA highlights.	2019-02-27
33	1.6.1 Patch and Statistics	Full 1.6.1 "Ironclad" patch log, info about the 1.6.2 beta and player statistics.	2019-03-13
34	1.6.2 Open Beta Patch	1.6.2 Open Beta Patch content and some AI naval screen statistics	2019-03-20
34	1.6.2 Update	1.6.2 Highlights and patchlog	2019-03-27
35	1.6.2 and Roadmap	1.6.2 release, future roadmap and announcement of 1.7 "Hydra" and 1.8 "Husky".	2019-04-03

Waking the Tiger

All developer diaries about the Waking the Tiger expansion and patch 1.5 (aka Cornflakes).

No.	Title and Link	Description	Date
1	Future and Cornflakes	Podcat shares the team's (non-exhaustive) list of features to act as a future development roadmap for HoI4	2017-08-23
2	Our development process	Sofia "KimchiViking" Höglund, HoI4's project lead, explains the development cycle, from design to implementation.	2017-08-30
3	A Product Manager's Role	"Firebolt", HoI4's product manager, on the intricacies of budgeting a game development.	2017-09-06
4	Chain of Command	Podcat on spicing things up in the HoI4 chain of command as part of patch 1.5	2017-09-13
5	Stability and War Support	Stability and War support to replace National unity in the next patch	2017-09-20
6	Division Namelists	Pallidum, HoI4's game designer, inserting some flavor (and logic) to division names.	2017-09-27
7	Synthetic Dawn	Refinements to synthetic refineries and inter-linking infrastructure with resources	2017-10-04
8	Bag of Tricks #1	Smaller improvements to the game: control groups, divisions consolidation, removal from faction, mini-map & pinging.	2017-10-11
9	A New Germany	Revised focus tree for Germany as part of requested alternate history options	2017-10-18
10	Bag of Tricks #2	Another small features and improvements, this time with relation to equipment	2017-10-25
11	Airplanes and Lootboxes	Further improvement of air related aspects	2017-11-01
12	Decisive Action	Adding decisions, missions, crises and special projects to the game	2017-11-08
13	Nationalist China	The 1st focus tree for China (the nationalist path) as well as the announcement of Waking the Tiger expansion.	2017-11-15
14	Communist China	The 2nd focus tree for China (the communist path) along with an example of the new decision system in action.	2017-11-22
15	Leaders, abilities and Traits	Revamped and expanded trait system and the mysterious "red phone" icon (aka command power).	2017-11-29
16	Acclimatization and Special Forces	Troops are now affected by hot and cold climates, and new changes to special forces.	2017-12-06
17	Border Wars: The Last Warlord	More detail on the Chinese warlords.	2017-12-13
18	Christmas & Modding	Modding guide for the new decisions & missions system in patch 1.5.	2017-12-20
19	New German Divisional Namelist	Further improvement of incoming German unit namelist.	2017-12-27
20	Japan rework	A rework of the Japanese national focus tree.	2018-01-03
21	Bag of Tricks #3	3rd assortment of small improvements: attachés, extra ground crews, historical army insignias, and volunteer air wings.	2018-01-10
22	Manchukuo	The last unrevealed focus tree for Waking the Tiger: "Manchukuo".	2018-01-17
23	War Changes and game Difficulty	Changes to 3-way war handling and addition of 2 more difficulty settings.	2018-01-24
24	Sound, Music and Art for Tiger	On the topic of the artistic additions to Waking the Tiger.	2018-01-31
25	Naval Updates	Improvements of naval matters: losses and kills overview, convoys raiding, transports interception, and more.	2018-02-07
26	Formable Nations and Achievements	New goals to strive for: formable nations and some 18 achievements.	2018-02-14
27	Performance and AI	Performance and AI.	2018-02-21
28	Recap Episode	What is coming in Waking the Tiger and the 1.5 Cornflakes.	2018-02-28
29	Pre-Release and International Women's Day	Women's contribution during the second world war.	2018-03-07
30	Post-Release patch	Info about patch 1.5.1	2018-03-14
31	1.5.2 Update #1	Info about patch 1.5.2: German border changes, commander XP gain changes, multiplayer desyncs, and more.	2018-03-21
32	1.5.2 Update #2 and Modding Goodies	Info about patch 1.5.2: Air Balance and Changes, Nukes and Surrender, Manchukuo, Modding and more.	2018-03-28
33	1.5.2 Update #3 and Telemetry	An updated beta and multiplayer telemetry	2018-04-04
34	1.5.2, Future Roadmap and Ironclad	The return of the bullet list and possible future development roadmap	2018-04-11

Death or Dishonor

All developer diaries about the Death or Dishonor country pack and patch 1.4 (aka Oak).

No.	Title and Link	Description	Date
1	Reflections and Romania	First look at new DLC content	2017-04-12
2	License production and map changes	1.4 Oak and the upcoming expansion will see map improvements and new ways of getting tech	2017-04-19
3	Announcement and AI Update #1	Announcement of new content pack coming with the free 1.4 Oak along with details on AI improvements	2017-04-26
4	Hungary	Hungary changes coming up	2017-05-03
5	Equipment Conversion & War Update	Repurposing old material and improvements to the war overview	2017-05-10
6	Air Improvements	Air combat overhaul in 1.4 Oak	2017-05-17
7	Yugoslavia and Air Zones	Yugoslavia unique flavor and more details on aerial combat overhaul in 1.4 Oak	2017-05-24
8	Czechoslovakia and AI Update #2	Let's have a look at Czechoslovakia and another AI update from Steelvolt	2017-05-31
9	Bits & Bobs	New subject levels, achievements, music, assorted QoL features and AI Update #3.	2017-06-07
10	1.4 "Oak" Changelog sneak peek	Patch 1.4, aka Oak, changelog.	2017-06-12
11	Post-release chat	Bugs, new and old, dealt with in the 1.4.1 beta patch.	2017-06-21
12	Meet some new people	Beta patch status, preliminary gaming statistics post DoD and introduction of new team members	2017-06-28
13	We're back!	New beta patch with additional fixes, more portraits for free and an interim solution to an old AI transport problem	2017-08-16

Together for Victory

All developer diaries about the Together for Victory country pack and patch 1.3 (aka Torch).

No.	Title and Link	Description	Date
1	Future Focus	Focus for 1.3 / upcoming expansion along with general plans for the expansions beyond	2016-09-23
2	The Team	Presentation of the current HoI4 team lineup	2016-09-28
3	Memory Lane	A look at how some concepts have changed over the HoI series, such as: supply, upgrades, reinforcement and more.	2016-10-05
4	Blitz Command and Garrison Orders	Blitz Command coming in the next expansion, garrison orders in the free patch	2016-10-12
5	Oh Canada!	Canada and the Commonwealth	2016-10-19
6	Ally Down Under	Australia updated in Together for Victory	2016-10-26
7	South Africa and Continuous focuses	South Africa and Continuous focuses	2016-11-02
8	Autonomy	New levels for subject nations coming in Together for Victory	2016-11-09
9	India - Struggle for Independence	A closer look at the changes coming for India in Together for Victory	2016-11-16
10	New Zealand & Combat Log	New Zealand focus and tech trees as well as a combat log	2016-11-23
11	Together for Audio	Music and Audio in Together for Victory	2016-11-30
12	Cosmetic tags, art, gameplay and AI	One week to the release of Together for Victory!	2016-12-07
13	TFV AI Update #2	Part 2 of AI bugfixes and updates for TFV	2016-12-09
14	TFV AI Update #3	Part 3 of AI bugfixes and updates for TFV	2016-12-12
15	TFV AI Update #4	Part 4 of AI bugfixes and updates for TFV	2016-12-14
16	Achievements & Patchlog	New Achievements and 1.3 changelog	2016-12-14
17	XMAS & Hotfix out!	It's time for holidays! Development diaries will be back again in 2017!	2016-12-21
18	Back from Christmas	1.3.2 hotfix patch soon in public beta	2017-01-11
19	Squanching them bugs	Planned changes for 1.3.3 and general focus for the 1.4 Oak patch	2017-01-18
20	Getting started with modding	Havebeard goes over modding requests and modding tips for beginners	2017-01-25
21	1.3.3 Modding Features	More modding features coming	2017-02-01
22	Patch 1.3.3 Update #1	Changes done to industry, world tension and capitulation in the upcoming patch	2017-02-08
23	Patch 1.3.3 Update #2	Details on QoL improvements, AI update, performance and optimizations done in the coming patch	2017-02-15
24	1.3.3 Patch #3	The patch should now be ready for release	2017-02-22

Post-release patches

All developer diaries about the post-release patches, patch 1.1 (aka Red Ball Express) and patch 1.2 (aka Sunflower).

Patch 1.1 (Red Ball Express)

No.	Title and Link	Description	Date
1	Release and Future	Podcat shares his thoughts on the release, as well as discussing the near future patches	2016-06-10
2	Red Ball Express	Tweaks to access to allied territory, peace conferences, invasions and naval bombers along with new battle plan modes upcoming in 'Red Ball Express'	2016-06-17
3	Summer Vacation	The team is going on a well deserved summer vacation	2016-07-01

Patch 1.2 (Sunflower)

No.	Title and Link	Description	Date
4	Back from Vacation	AI changes and MP hotjoin in 1.2, aka 'Sunflower'	2016-08-05
5	Custom Difficulty Settings	AI improvements and implantation of custom difficulty settings at game setup	2016-08-12
6	Sunflower (patch 1.2)	Port Strikes and AI improvements to upgrading templates and naval missions coming in Sunflower	2016-08-19
7	New Releasable Nations	A look at new releaseable nations and more of the AI improvements coming in Sunflower (patch 1.2)	2016-08-26
8	Sunflower Improvements	Sunflower updates: GUI improvements, naval balance, focus trees	2016-09-02
9	Bugs and Stats	Readying Sunflower for release and sharing some gameplay stats	2016-09-09
10	Sunflower is Live	Patch 1.2 is out live, next patch is 1.3 aka "Torch"	2016-09-16

Base game

All developer diaries about Hearts of Iron IV (base game).

No.	Title and Link	Description	Date
1	Our Vision	Design goals	2014-02-07
2	The Tools of War	Equipment, production and research	2014-03-07
3	Bringing WWII to the mainstream	Dogs!	2014-04-01
4	Land Doctrines	Doctrine paths	2014-04-11
5	Production Lines	How things get built	2014-05-09
6	Division Design	Division planner, division template	2014-06-13
7	Air Combat	Air war	2014-07-11
8	Experience and Variants	Production	2014-08-08
9	Vacation and Air tech	Air technology tree	2014-09-12
10	Naval Combat	Naval gameplay	2014-10-10
11	Map & Graphics	Visual aesthetics of the game	2014-11-07
12	Internal Politics	Internal affairs of a country	2015-01-16
13	Conscription & Training	Manpower, recruitment, training	2015-02-20
14	National Focuses	National focuses	2015-03-20
15	On the high seas	Naval battles	2015-04-11
16	World Tension	World tension, war justifications	2015-05-08
17	Johan Invades Germany	Barely a dev diary	2015-06-12
18	Army Planner	Creating and deploying units	2015-06-26
19	Equipment	How equipment works	2015-07-03
20	Soviet Union and Communism	Soviet Union and Communism	2015-08-14
21	Land Combat	Land combat mechanics	2015-08-21
22	Support Companies	List of support companies	2015-08-28
23	Industrial Capacity	How factories function	2015-09-04
24	Trade and Resources	Overview of international trading	2015-09-11
25	Laws and Politics	How to manage government	2015-09-18
26	The Navy	Naval doctrines and naval technology	2015-09-25
27	Italy	Italy's situation in the game	2015-10-02
28	Weather & Terrain	How weather and terrain function	2015-10-09
29	Factions & Wargoals	How factions and wargoals function	2015-10-16
30	France	Overview of France	2015-10-23
31	Peace Conferences	Ending wars	2015-10-30
32	The USA	Overview of USA	2015-11-06
33	Supply	The supply system and supply areas.	2015-11-13
34	Civil Wars	Civil Wars and Coups.	2015-11-20
35	Germany	Overview of Germany	2015-11-27
36	Helping out in other wars	Helping out in other countries wars without directly getting involved	2015-12-04
37	Carrier Warfare	How aircraft carriers work.	2015-12-11
38	Submarines	How submarines work	2015-12-18
39	The Radio	Radios, reinforce chance and radar stations.	2016-01-08
40	Changes to the game	Completely revised factory slots mechanic, World Tension..	2016-01-15
41	Order of Command	OOC and Commander traits	2016-01-22
42	Japan	Overview of Japan	2016-01-29
43	Diplomacy and other options	Diplomacy, Factions, War Goals, ... also: HOI4 is now in BETA	2016-02-05
44	Occupation and Resistance	Managing occupied territory	2016-02-12
45	Battle Plans	How battle plans work	2016-02-19
46	United Kingdom	Overview of UK	2016-02-26
47	China	Overview of China	2016-03-04
48	Naval Invasions	How naval invasions work	2016-03-11
49	Nukes!	Atomic bomb - Research and requirements for production and use	2016-03-18
50	Generic Focus Trees	Generic Focus trees and DDR mat support	2016-04-01
51	Sound & Music	Music & Sound Design in Hearts of Iron IV	2016-04-08
52	Modding	A look at the improved modding support in Hearts of Iron IV	2016-04-15
53	2D art	Sideburnout talks about the 2D graphics of Hearts of Iron IV	2016-04-22
54	AI	SteelVolt speaks of the topic no one wants to touch, but everyone wants to know about	2016-04-29
55	QA	A closer look into the QA process when developing Hearts of Iron IV	2016-05-06
56	Bits & Pieces	Mopping up a bunch of smaller topics not covered in other Development Diaries	2016-05-13
57	Poland: United and Ready	About the free DLC shipped with all copies of Hearts of Iron IV	2016-05-20
58	Tutorial, Wiki & Browser	A look at the tools we provide to help you learn how to play Hearts of Iron IV	2016-05-27
59	D-day	A short, final message from Podcat before we release	2016-06-03

Videos

Developer video diaries and developer's let's play sessions on the various expansions.

Videos

No.	Title and Link	Description	Date
1	Hearts of Iron 4 Live streams	Earlier previews of Hearts of Iron IV by the devs mixed with Q&A	2014-08-18
2	Hearts of Iron 4 #1 - Grand Ambitions	Johan Andersson, Dan Lind, Mats Virtanen, and Jakob Munthe discuss the design and ambitions of the fourth installment of the Hearts of Iron series.	2016-03-15
3	Hearts of Iron 4 #2 - Naval, Land and Air Power	Johan Andersson, Dan Lind, Mats Virtanen, and Jakob Munthe discuss the different types of warfare and how they're used in Hearts of Iron IV.	2016-05-12
4	Hearts of Iron IV - Beginner Tutorial	Jake (aka DDRJake) hammers HoI4 beginner tutorials in a soothing, calming voice	2016-05-30
5	Hearts of Iron 4 #3 - Politics and Coups	Johan Andersson, Dan Lind, Mats Virtanen, and Jakob Munthe discuss on the political interactions in Hearts of Iron IV.	2016-06-01
6	PDX FanGathering 2016	A sneak MP peak at the new HoI4 Together for Victory expansion at the 2016 PDX FanGathering	2016-12-02
7	Together for Victory - Feature Spotlight	Dan "Podcat" Lind speaks on the upcoming Together for Victory country pack and patch 1.3	2016-12-07
8	Death or Dishonor - Release Trailer	Release trailer detailing the features of the Death or Dishonor DLC for Hearts of Iron 4.	2017-06-14
9	Tutorial #1 - Interface Overview	An in-depth interface tutorial with Daniel "Da9L" Sjöberg and Christian Daflos (community manager).	2017-10-25
10	Tutorial #2 - Trade, Production, Division Templates	The 2nd part of the tutorial this time covering trade, production, and division templates. With Daniel "Da9L" Sjöberg and Christian Daflos (community manager).	2017-11-01
12	Waking the Tiger #1 - China	Dan "Podcat" Lind and Gabriel Blum with details on the expanded representation of the Chinese fronts.	2018-01-30
13	Waking the Tiger #2 - Germany & Decisions	Dan "Podcat" Lind and Drikus Kuiper with details on alt-historic path in the German focus tree, the new decision system, as well as new mechanics around stability and war support.	2018-02-01
14	Waking the Tiger #3 - Chain of Command	Dan "Podcat" Lind and Kandra Dahlgren with details on the new Chain of Command mechanic and commander traits, the new command power mechanic and division namelists/insignias.	2018-02-07
15	Hearts of Iron IV - Patch 1.5 "Cornflakes"	Dan "Podcat" Lind expands on the free 1.5 patch (aka Cornflakes) accompanying the Waking the Tiger expansion.	2018-02-09
16	PDXCon 2018 - News From The Front	Dan Lind, Game Director of Hearts of Iron IV, discusses the future of HOI and its upcoming update Man the Guns.	2018-05-20

Let's Plays

No.	Title and Link	Description	Start date	End date
1	World War Wednesday	Daniel Sjöberg (replacing Jakob Munthe as Nazi Germany) faces off against Johan Andersson (as Jolly England) in the war of the century, testing out the ins and outs of Hearts of Iron IV	2015-12-02	2016-03-10
2	World War Wednesday - Pre-release	Jake and Daniel showcasing single player campaigns and co-op nations	2016-03-17	2016-06-23
3	The Three Day War	Multiplayer event of HoI4 where devs and youtubers vying for dominance	2016-06-14	2016-06-16
4	Together for Victory - Launch Dev MP	Together for Victory feature stream by Dan and Daniel	2016-12-08	2016-12-14
5	Death or Dishonor	Daniel "Da9L" Sjöberg and Dan "Podcat" Lind taking a sneak peak at the upcoming HoI4 Country Pack	2017-04-26	2017-06-15
6	Chain of Command	Multiplayer event of HoI4 where devs and youtubers vying for dominance	2017-08-16