The Best Diplomacy Mods for Stellaris (All Free)

This post may contain affiliate links. If you buy something we may get a small commission at no extra cost to you. (Learn more).

Half of your job as leader of a spacefaring civilization is managing your relationship with your galactic neighbors before they decide to handle it for you.

You can make friends with others, treat them as trading partners, or try to bully them into giving you what you want without having to lose a single ship. The possibilities are numerous, like the stars in the night sky.

But Stellaris’ diplomacy’s complexity leaves a lot to be desired – especially if you’re used to other Paradox titles like Europa Universalis IV, which offer very complex international political ecosystems.

Many mod creators have tried their hand at improving this aspect of the game – and there are some gems you can’t miss out on.


10. Agreements Boost Diplomatic Weight

Agreements Boost Diplomatic Weight Mod for Stellaris

Check Out This Mod

Stellaris lets you create mutually beneficial agreements with other empires, such as Commercial Pacts, Defensive Pacts, and Migration Treaties.

It makes sense that these agreements should strengthen your bonds with your neighbors and project strength to the broader galactic community.

Agreements Boost Diplomatic Weight makes this a reality in Stellaris by significantly increasing your Diplomatic Weight depending on each deal and pact you maintain with another empire.


9. AI Spymaster

AI Spymaster Stellaris mod

Check Out This Mod

The AI in Stellaris is famous for being incompetent in some of the finer points of galactic conquest.

One of these is espionage and, truth be told, the entire envoy system.

AI Empires will often appoint one or two envoys to Federations or the Galactic Community and sometimes even send out a spy. Still, they never get anything done – and there are always some envoys sitting around collecting a salary without actually working.

The AI Spymaster mod makes the AI much better at managing their spy network, sending them out to the most profitable spy networks so they can steal your research or extort favors out of you.


8. Espionage Operations: Influence Ethics

Espionage Operations: Influence Ethics Mod for Stellaris

Check Out This Mod

Throughout history, nations have attempted to bring their neighbors to their way of thinking – either by force or less conspicuous means.

This mod opens the doors to applying ideological pressure on your neighbors through your spy network by using the “Influence Ethics” operation.

Over five years, your Envoy will nearly double their Ethics Attraction toward your empire’s ideology. It’s not guaranteed to change their governing Ethics to yours, but it’ll definitely affect their politics.

This can also be done to you – so you better keep those politicians happy!


7. StarTech AI

StarTech AI Stellaris mod

Check Out This Mod

One of the biggest problems in vanilla diplomacy is that military alliances are only good for intimidation.

The vanilla AI is bad at cooperating in any joint wars – even the ones they start themselves, leaving you to fight to the death to save your Federation from being humiliated.

StarTech AI is a comprehensive enhancement of the AI that makes them much more aggressive and better at developing their tech and economy.

With this installed, you’ll have to take diplomacy much more seriously. Not only are other empires great allies in the war, but they’ll also seize any chance to bring their fleets to your space.


6. Expanded Xeno Diplomacy

Expanded Xeno Diplomacy Mod for Stellaris

Check Out This Mod

Have you ever felt politically limited by the policies and edicts available in vanilla Stellaris?

Expanded Xeno Diplomacy solves the issue by introducing three new policies and nine new edicts that open the door to interesting political maneuvers.

Some of my favorite new Edicts include State Projection, which increases your Diplomatic Weight from all sources, and Directive Endgame, which gives you bonus trust from your allies and greater damage against endgame threats.

The different policies are also an excellent addition, and they’ll let you orient your diplomacy toward domination or cooperation more effectively.


5. Galactic Community Expanded

Galactic Community Expanded Stellaris mod

Check Out This Mod

I love playing as a Fanatic Pacifist, so making my way to the top of the Galactic Community through my connections (and impressive R&D) is a vital part of my strategy.

Regrettably, the Galactic Community is somewhat limited in its reach.

It’s an interesting concept, but it lacks more content to make it as engaging and useful as it could be.

Galactic Community Expanded greatly improves this diplomatic mechanic by introducing many new resolutions and fixing some bugs present in the original.

You can now declare a Crusade against machine/synthetic empires after passing the Crusade Against the Heretic resolution or freeze pop growth through Galactic Pop Controls. And that’s just the tip of the iceberg!


4. Diplomatic Expansion Series

Diplomatic Expansion Series Mod for Stellaris

Check Out This Mod

The Diplomatic Expansion Series is a collection of mods emphasizing non-armed conflict and conquest, mimicking how politics work in the modern world.

For example, the DE: Hegemony mod lets you invest in foreign countries to exert influence over them, form treaties and organizations within the Galactic Community, and influence your neighbors’ ethics.

Another great one is DE: Penetration, which lets you fabricate claims to their systems and even plot political assassinations on foreign soil. That’s what I call realism.


3. Potent Rebellions

Potent Rebellions Stellaris mod

Check Out This Mod

Armed rebellions are what every world leader fears the most.

And when your empire spans several systems and includes all kinds of different races, things can get hairy very quickly.

While rebellions were already part of the game in vanilla Stellaris, they’re somewhat lackluster – and easily handled by any large empire.

Potent Rebellion changes that by making insurgent rebellions much more common and considerably more effective.

The new rebels are often backed by foreign powers and seek to join them, and every successful rebellion will send ripples through your other colonies, stoking the flames of unrest.


2. Dynamic Political Events

Dynamic Political Events Mod for Stellaris

Check Out This Mod

While it doesn’t directly change the diplomacy system, Dynamic Political Events is a crucial addition if you want to make space politics fun.

This mod adds a wide variety of exciting new events related to domestic and foreign politics. This includes primitive civilizations sending probes to your observation posts, xenophobic governors becoming involved in Xeno sex scandals, and more.

Get ready to put down faction revolts, deal with international scandals, and struggle to maintain political control over your colonies as you head into 55,000 words of political events.


1. Expanded Espionage and Diplomacy

Expanded Espionage and Diplomacy Stellaris mod

Check Out This Mod

Some of the most meaningful reforms to Stellaris diplomacy are the Expanded Espionage and Diplomacy mod.

This add-on is built upon three main pillars:

  • More complex international relations
  • Federation and Galactic Community enhancements
  • A wealth of new espionage operations

Other empires will now hold opinions on almost any aspect of your empire management, from policies to ascension perks and everything in-between, making the international community a tad more realistic and hard to exploit.

Federations are now more beneficial, and many new resolutions are added to the Galactic Community, including establishing the Galactic Republic (for those who don’t like hoarding power).

Browse: Video Games

Nelson Chitty

Nelson Chitty is a Venezuelan expat living in Argentina. He’s a writer and translator passionate about history and foreign cultures. His ideal weekend is spent between leisurely playing games of Civilization VI and looking for the next seinen anime to marathon.