What Is Europa Universalis IV Aggressive Expansion?


I haven’t played this game for a while. One of the first things I noticed that I don’t remember about it is aggressive expansion. Seemed important so I started digging around and here’s what I found.

Aggressive Expansion is a negative modifier on diplomatic relations between you and another country. The Aggressive Expansion number is regional and is different for each nation. Once a country’s Aggressive Expansion opinion towards you exceeds 50 they could either start or join a coalition against you.

When you first start a game your Aggressive Expansion opinions with other nations will be zero. Once Aggressive Expansion increases and stays high long enough, countries will hate you (become outraged) and will even become your enemy. It can drive them into either joining or creating a coalition of nations that will stand against you. Aggressive Expansion is always something you will have to deal with as your country grows and annexes those unruly territories next to your borders. After all, your citizens deserve peace and security, right?

One way Aggressive Expansion is increased is by annexing regions. If you have an Aggressive Expansion number of 50 or higher with a country plus have negative relations with them their attitude will change to outraged and they might start or join a coalition against you. You can counter this by improving relations with them through diplomats and diplomacy.

Minimizing The Penalty For Aggressive Expansion

One way to minimize Aggressive Expansion is to take small chunks of land instead of making a major land grab. Whenever you annex territory you get an Aggressive Expansion penalty from nearby countries, so taking less territory all at once can sometimes result in a lower opinion number. Do your best to keep the Aggression Expansion number below 50 so coalitions won’t form against you. Another way to keep it from increasing too much is to ally with the major countries close to you. Expanding into different parts of the world helps too, this can spread out Aggressive Expansion over different continents.

The Aggressive Expansion penalty is increased by annexing provinces, forcing regions to become your vassals, declaring wars that lower your stability, like declaring war without a casus belli, or by breaking a truce. It can be also increased through any similar actions one of your vassals may take.

It can be greatly increased by demanding territories or vassals during a peace deal. Having a covert action uncovered is another way it increases.

If you have the same religion as the territory you’re trying to annex the modifier is 50% more, 0% for heretics, and is reduced by 50% for those heathen who don’t agree with you. Culture plays a role too with an additional penalty of 50% if they have the same culture as you, 0% for an unrelated culture, and 25% for a different ethos that’s part of a culture that’s the same as yours. The Casus belli modifier is 100% for Conquest, 75% for Imperialism, and 25% for Reconquest.

The aggressive expansion penalty slowly decreases over time unless you do something to destabilize things in the region. Aggressive Expansion is raised or lowered through religion, culture, administrative efficiency and having a casus belli for a war. The rate it decreases can be influenced by ideas or advisors that provide “better relations over time.” The Cleansing of Heresy Casus Bellis reduces the aggressive expansion penalty by 25% as well.

Sometimes those unruly territories you’ve gracefully allowed to join your empire just don’t appreciate it and want to rebel. To help reduce that possibility increase autonomy in those conquered provinces. This reduces the threat by 10 but it means less tax revenue and less manpower gains. Another way to avoid rebellions is to implement Feudal De Jure Law. This will usually improve local autonomy by up to 75%. You can also station an army in the territory.

How To Find The Aggressive Expansion Opinion

There is no map mode for checking Aggressive Expansion opinions but the coalition map mode can be used to find it and you’ll probably need to change map modes to see it. The coalition map mode is found in the Diplomatic Map Mode group and it can be identified by the dove icon. Once you click on that icon a list of diplomatic map modes will come up on the screen. The Coalition map mode will be about the fourth option down on the list, represented by an icon with a red and blue flag crossed over each other with a sword in between them. Once that map mode is active hovering the cursor over a country will tell you what their opinion is about your aggressive expansion.

Claims can reduce Aggressive Expansion if the correct Casus belli is used, but generally having a claim on a region won’t have any effect on Aggressive Expansion. If the Excommunicated casus belli is used Aggressive Expansion is reduced by 50%, if the Government Form War casus belli is used Aggressive Expansion is reduced by 25%.

Other Things To Keep In Mind About Aggressive Expansion.

  • Already mentioned but worth mentioning again, Aggressive Expansion is calculated on a per country basis.
  • A good strategy is to conquer territories so other countries can’t expand.
  • Allies don’t care too much about your Aggressive Expansion so that opinion won’t increase very much with them, as long as you’re not aggressive with them that is.
  • If you’re annexing regions of the Holy Roman Empire the Aggressive Expansion opinion against you increases much faster.
  • Aggressive Expansion varies with distance. The farther away a country you’re at war with is from another country the less they care and the less the Aggressive Expansion penalty.
  • You can check out the how much a peace deal affects you before entering one by taking a look at the Peace Negotiation screen prior to accepting the deal.
  • It’s best to expand in different directions. This reduces the overall increase in the Aggressive Expansion opinion.

How Do You Claim a Territory In Europa Universalis 4?

The most basic way to claim territory is to fabricate a claim. You fabricate a claim by creating a spy network in a province that’s adjacent to your nation or within one sea zone of your territory, each country must is at peace with the other one. The exception to this type of claim is if you’ve completed exploration ideas, then a claim can be fabricated in colonial regions that aren’t adjacent to your territory. The claim only lasts 25 years unless you are already at war with the country you’re trying to take the region from, or if it is a permanent claim.

A permanent claim can only be established through a national decision, national event, or a mission. A permanent claim is exactly that, permanent unless revoked through a war or some type of special event. Temporary claims are much more common.

What Is a Coalition?

A coalition is a group of nations who are worried about your assertive expansionism at the expense of diplomatic relations. They’ve decided they need to present a unified front against in order to stop your aggression, which they perceive as a threat to all of them. If you fight one member of a coalition you will end up fighting them all, which is one of the strengths of a coalition. If one of them declares war on you you’ll most likely end up fighting all the other countries as well. If there are 3 or fewer offended countries a coalition will not form.

When planning to annex a region you will see a range of numbers in the tooltips. The range means one country will get the minimum number and another country will get the maximum number with other countries falling in between those numbers if there are any.

What Does Administrative Efficiency Do EU4?

Among a lot of other beneficial things Administrative Efficiency reduces the penalties of Aggressive Expansion. It can also help your nation integrate conquered regions gracefully and helps reduce over extension. The higher this number is the more territory you can conquer. You can increase Administrative Efficiency through advances in technology.

Clicking on an alert or on the Country View icon will bring up a panel with numerous tabs. You can see Administrative Efficiency by clicking on the Stability and Expansion tab. Once there, hover the mouse cursor over Administrative Efficiency  percentage number under the Administrative Icon (red and green arrow). Hovering over the percentage number will give you a breakdown of your Administrative Efficiency.

How Do You Get a Casus Belli?

A casus belli is simply a justification to go to war and you can get one in several ways. The easiest method is by fabricating a claim with a spy network. You can start a war without a casus belli but it increases the Aggressive Expansion number significantly by 30 and lowers stability in a region by an additional 2. A list of available casus belli becomes available when declaring war. After selecting a casus belli you’ll be asked to choose a war goal.

Rich Gallien

I've always liked board games like chess and PC games, especially space based strategy games, which lead to the creation of this site. I hope you enjoy it as much as I enjoyed creating it and updating it with new games!

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