Managing Aggressive Expansion while avoiding a Coalition

I just want to live and conquer in peace!

And therein lies the problem :) As France, it's not very difficult to be universally hated, due to its central position and multiple powerful neighbours. You have probably accumulated too much aggressive expansion(AE) from conquering left and right (particularly provinces these superpowers consider part of their rightful domain) and everybody's outraged or hostile. There's a reason why AE is sometimes referred to as "badboy" :-)

It happens. What you need to do is find powerful allies to keep an armed peace, not unlike the Cold War. Hungary and Poland/Commonwealth are good choices, the latter mostly useful against Austria. Some of the Scandinavian powers can help with England's fleet. Larger HRE princes that do not border you can also be of assistance -- Savoy, Brandenburg, Bohemia are typically strong contenders. Generally, you need to be looking for allies among coalition's bitter enemies. Declare some of the stronger coalition members as your rivals (they hate you anyway), and placate, bribe and befriend their enemies into allying with you. Doesn't matter if they are not very powerful by themselves, they have friends of their own that might help. And for all that is holy, don't participate in wars on the aggressor side until tensions are eased.

The take-home lesson is to be careful when expanding. Don't take too much provinces in one go, prefer vassalizing and releasing small nations, and always check how much AE your current peace offer will cause. It takes a long time before coalitions dissolve, typically more than the duration of a truce, so it's preferable to take small bits at a time to keep everybody happy.

You are indeed right that aggressive expansion (AE) is a major obstacle to military expansion: it is what brings balance to the game and allows smaller nations to become successful and beat much more powerful rivals. Otherwise, superpowers can grow unchecked which makes for rather uninteresting games.

At any rate, there are other ways to go:

• Diplomatic vassalization. This is typically the preferred strategy bar none, if your regional situation allows it. You placate, bribe, ask, threaten your targets into accepting vassalization peacefully.

  Preferably, most of the conditions below need to be fulfilled for it to be effective, or indeed possible:

  • Monarchy type government, as most republics (except Dutch and Noble Republic) cannot enter into royal marriages.
  • Same religion as your intended targets, or at the very least, same religious group.
  • Region with a large number of small countries (Indian subcontinent and Central Europe are prime examples), while you are moderately large or the 800-pound gorilla in the room.
  • Preferably, some diplomatic bonuses from your country's ideas (extra relations and more importantly, diplomatic reputation).
  • Works best if you rarely, if ever, take territory directly in a military conflict.

  The 190 reputation needed can be a challenge to build, particularly if you share a land border with them, but there are many ways to increase your standing with them. Diplomatic vassalization is only possible to propose to countries that have less than 40 total tax base (your own tax base needs to be significantly higher than theirs).

• Military vassalization. Reserved for countries that just won't see eye to eye to you in terms of your global domination and need to be persuaded gently with a stick, shooting or other. Most of the restrictions applying to diplomatic vassalization are not applicable here: you can vassalize any sufficiently advanced country with any form of government or religion, provided they are small enough to have province score in a war less than 100%.

  Some tips:

  • Fabricate claims to as many provinces as possible: this reduces warscore cost and can mean the difference between success and failure to vassalize the target wholesome.
  • Preferentially look for vassals with many uncontested cores (perhaps lost in previous wars). You cannot wage war for them with other countries, but you can demand they are returned to your vassals as a part of a peace treaty.
  • Full annexation and immediate release of a vassal will wipe any accumulated AE and other negative modifiers, and will spawn them with your state religion.
  • Some casus belli (CBs) require smaller warscore to offer subjugation.

The diplomatic game can be much more satisfying and rewarding in EUIV, and can bring immense variety and depth to the game.

Further information with more strategic and tactical tips is available on EU4wiki:

• Vassals
• Casus belli