Hearts of Iron IV Guide: Division Templates, Combat Width and 2026 Meta

What is HOI4, and who is this guide for?

Hearts of Iron IV (Paradox Development Studio, 2016) is a grand strategy game in which you lead a country through World War II between 1936 and 1948. You build your industry, design your army, weave alliances and manage fronts. It's faster and more war-focused than EU4: you either rewrite history or change it completely.

This guide is written for players who have just opened the game or who fall apart in their first war. HOI4 is overwhelming if you try to learn everything at once; that's why this guide first makes clear what to learn in what order, then prepares you for division design and encirclement tactics.

Current status & must-have DLCs (2026)

Unlike EU4, HOI4 is <strong>still actively developed</strong> and gets regular updates. As this guide was being written:

• Current version: 1.19.2 (June 2026).
• Latest major release: 1.19, which arrived with the Thunder at our Gates DLC.

Learning priority order and core mechanics

The most critical thing in HOI4 is not trying to learn everything at once. Follow this path in order of impact:

1. Division Templates — Highest impact. The basic building block of your army; you can try it with the explorer below.
2. Focus Tree — The country's roadmap; you manage bonuses and events from here.
3. Production — First civilian factories (compounding benefit), then military factories for weapons.
4. Construction + Supply/Logistics — Your army is useless if it isn't fed.
5. Air Superiority — Affects land combat by ±20%.
6. Political Power — Funds advisors, laws and focus choices.

The 5 best starting countries for beginners

7 common mistakes and the first-game flow

The 7 most common beginner mistakes

1. Going on the offensive without air superiority.
2. Neglecting supply/logistics and starving your divisions to nothing.
3. Trying to invade the USSR in winter.
4. Neglecting coastal defense and eating an enemy naval invasion.
5. Playing a demanding minor before learning the core mechanics.
6. Producing bombers before fighters — control the sky first.
7. Attacking level-5+ fortifications head-on — your losses multiply.

Where to start: the first-game flow

1. Learn the division template menu (15–30 minutes; the most important investment).
2. Practice basic land combat on the Western Front.
3. Establish air superiority with fighters.
4. Read the focus tree to understand the country's plan.
5. Actively manage your supply lines.

Division template explorer and combat width

• Good general widths: 18 / 27 / 35 / 42.
• The safest defaults in practice: 27 (infantry) and 35 (tanks/general front).
• 35 is a good choice for the Russian and North African fronts, and for tanks.
• 40–45 for large "breakthrough" divisions.

Click a template in the explorer below; its width, composition, when to use it and its strengths/weaknesses will open in the panel.

Encirclement, naval invasion and air superiority

Encirclement: the main war-winning tactic

In HOI4, wars are won by encirclement, not head-on pushing. You wrap tank spearheads around the back of the enemy line and cut off several divisions from the front; encircled divisions run out of supply and surrender — the enemy army melts away while you advance with minimal losses.

Naval invasion step by step

• You need ≥50% naval supremacy in every sea zone the invasion route crosses.
• Naval supremacy is boosted by your navy + air superiority.
• For island nations like England or Japan, naval invasion is a must.

1. Send your navy to the target sea zone.
2. Get naval supremacy to 50%+.
3. Support it with air superiority.
4. Plan the naval invasion order.
5. Launch it once preparation is complete.

Air superiority: why is it decisive?

• Superiority in an air region affects land combat there by ±20%.
• It also contributes to naval supremacy (critical for naval invasion).
• Clear the sky with fighters first, then add close air support (CAS).

Frequently asked questions

Which country should HOI4 beginners start with?

The best choice is Italy: it forgives mistakes and the Abyssinian (Ethiopian) war teaches core tactics in a safe setting. If you want a calm, pressure-free learning experience, the USA is a complete sandbox thanks to the protection of two oceans. If you're after a strong, hard-to-sink country, Germany is a good alternative. Play your first game with the 1936 start and Historical AI Focus on.

What should HOI4's combat width be? (2026)

In 2026 there's no single magic combat width; the old "40 is mandatory" advice no longer holds. The current version has widths that vary by terrain. The safest defaults in practice are 27 (infantry) and 35 (tank/general front). 35 works well for the Russian and North African fronts, and 40–45 for large breakthrough divisions.

Which DLC is a must for HOI4?

There's no single mandatory DLC. The expansions that enrich the experience the most add a focus tree for major countries. If you're just starting out, play the base game and free updates first; once you attach to a country/scenario, get the DLC that adds that content.

What's the current version of EU4 and HOI4?

As this guide was being written, HOI4 was still being actively developed; the current version is 1.19.2 (June 2026) and the latest major DLC was Thunder at our Gates. EU4, on the other hand, is "finished" at 1.37.5 (October 2024) and no longer receives new content. If you're starting out with HOI4, it makes sense to play the base game and free updates first and add DLC as you need it.