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HOI4 (Hearts of Iron IV): How to Naval Invade

HOI4 (Hearts of Iron IV) How to Naval Invade

Hearts of Iron IV (HOI4) is a World War II grand strategy game released in 2016 and developed by Paradox Interactive. With iconic landings such as the invasion of Normandy, Okinawa, and Sicily, to name a few, it is no wonder why naval invasions are a key part of the game’s mechanics. They are especially important when you need to attack island nations such as the United Kingdom and Japan. In this article, we’ll be going through how to naval invade in HOI4, the requirements needed to establish naval supremacy in key areas, and some great tips to keep your troops alive throughout the invasion.

How to Naval Invade in HOI4 – Naval Invasion Guide

To proceed with a naval invasion in HOI4, one must first set a plan to invade. You can do this by selecting an army (not an army group because they do not have the capability) and clicking on the anchor icon to the left. 

After that, you will need to select a port of departure and where you want to land your forces. It can be a single location or multiple ones, the choice is yours but this is where the simplicity of events end.

Capacity and Preparation Time

Once you have selected a plan of attack, now is the time to prepare for said naval invasion in HOI4. Let’s look at the invasion capacity and preparation time.

If a nation starts without any naval invasion technology, it will not be able to launch any invasions. To solve this, you need to start researching Transport Ship to be able to assign 10 divisions to a naval invasion.

The subsequent Landing Craft and Advanced Landing Craft technologies will add 40 and 100 to the division limit, respectively. Some land doctrines (Grand Battleplan) and the Spirit of the Army can also increase the capacity of a nation.

The invasion capacity of a nation in HOI4 is based on the number of divisions and is not limited to just a single invasion, meaning a nation can launch multiple naval invasions provided it doesn’t exceed its naval capacity. It also means that a division can be as big as possible and still only count as one in the grand scheme of things.

As with all plans, naval invasions take time to prepare in HOI4. Typically, a division will take 7 days to prepare for an invasion, though this can be reduced once you research the Landing Craft technology. Likewise, a general with the invader trait can use his commander ability to speed up preparation times.

Convoys and their Capacity

To transport your troops and naval invade in HOI4, you will require a sufficient number of convoys to do the task for you. Depending on the weight of the division, you may see some units needing a lot of convoys just to transport them. The general idea here is that the lighter the unit, the fewer convoys are needed.

Support companies, infantry battalions, cavalry battalions, and motorized vehicles require the least number of convoys, while tanks, mechanized units, and armored cars require the most number of convoys.

Naval Supremacy

To naval invade in HOI4, you require at least 50% naval supremacy over the areas where your invasion will be going through. If you do not have naval supremacy in the area, your troops will not move at all.

There are three naval missions that can help maintain naval supremacy in the area: PatrolStrike Force, and Naval Invasion Support. Out of all three, it is better to use the last, as they will directly accompany your invasion force and guard it against any submarine attacks.

There are three major ways to increase naval supremacy: Naval PowerAir Power, and Mines. To explain the three, see down here:

  • Naval Power – the larger the ship, the more supremacy it contributes. Your navy will be your primary focus, as it will be the best force to both control the seas and support your forces.
  • Air Power – the air superiority of the region will contribute directly as well to naval supremacy. The greater the air superiority in the region, the greater the bonus to the naval supremacy of your ships.
  • Mines – they will increase naval supremacy for your side as they do not affect friendly ships but only enemy vessels.

As long as you have +50% naval supremacy, a naval invasion can be launched immediately. Once the troops are already en route, it does not matter if the naval supremacy dips below 50%, as the troops will continue regardless.

And that is all you need to know about how to naval invade and how naval invasions work in HOI4. Check out other interesting HOI4 guides and articles:

Based in Santa Rosa, Philippines, Jonathan Ledesma is a Freelance Writer for Raider King.
Jonathan Ledesma
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