Europa Universalis Development Diary #5

Diplomatic Relations

Even if January is well under way, I will take the opportunity to wish everyone a Happy New Year! The Development Diary is back after a break, and this time we will take a look at Diplomatic relations. In simple terms there are two main categories of diplomatic relations, inter player relations, and relations between Player Realms and Non-Player Realms (NPRs). The first is to a large degree something that depends on oral agreements, threats and promises that are not bound by game mechanics. Today we will be talking about the latter, which is controlled by a set of rules.

English and Castilian Influence (cubes), Royal Marriages and Alliances in Iberia. 

Influence and Diplomatic Monarch Power

As a player, your diplomatic relations with NPRs will depend on how you invest your Diplomatic Power (DP). One of the Diplomatic Actions you can take is to place Influence in Areas on the board. You can do this by simply placing tokens (cubes) directly from the DP available (on your player mat) and onto the board, or you can pay with Ducats instead and take tokens from your supply. You may place Influence in Areas bordering your Realm, or adjacent to Influence you already have on the board.

Influence signifies political power and good relations in Areas that you do not control directly. Having sufficient Influence will enable you to perform a number of Diplomatic Actions, like forging Alliances, vassalizing or, eventually, even annexing other Realms. Since there is a cap on Influence in each Area, you may also, to a certain extent, use Influence to prevent other players from performing these Actions in your sphere of influence. If you maximize your Influence in an Area you automatically gain an Alliance or a Royal Marriage with a Realm in that Area.

Influence can be sabotaged by the spies of other players, and may also be affected by Wars and Events.

Royal Marriages

A Royal Marriage is a bond that strengthens your political foothold in Areas of the Realm you have marriage ties to. Royal Marriages makes it harder to sabotage your Influence and they are also required for a number of (mostly beneficial) Events to trigger. With enough Influence, a Royal Marriage may, given the right circumstances, position you to inherit the throne of another Realm. You can gain a Royal Marriage using the appropriate Action Card, by Events, or by maximizing your Influence in an Area.


An Alliance is a pact to support one another in the event of War. If someone attacks you, your ally will happily support you with troops. When your ally is under attack, you must support them, or suffer a penalty for being disloyal. If you attack another Realm, you may convince your ally to join you by spending Influence. When you bring an NPR ally into War, you will control their forces for the duration of the conflict. 

An Alliance is also a prerequisite for subjugating another Realm diplomatically, and thereby making them a Vassal. As with Royal Marriages, there is a corresponding Action Card, and you may gain Alliances through certain Events, or by maximizing Influence.


Polish and Ottoman Vassals (tokens without flags).

Vassals are subordinate Realms that have limited independence. They pay a portion of their income to their overlord, as well as providing troops when requested. In time a Vassal may be politically Annex­ed by their overlord. Certain Events may cause Vassals to break free from the ties to their overlord.

To vassalize one of your Allies diplomatically, you must have sufficient Influence in their Home Areas. You must also have a Tax Income that is greater than their’s. To complete the process, you play the Vassalize/Annex card and remove the required Influence from the target Realm. When you have a Vassal already, you may follow the same procedure to annex them diplomatically, thus completely integrating them into your Realm.

Read the previous Development Diary chapters here:

Development Diary #1 (Map Board)
Development Diary #2 (Box Art and Monarch Power)
Development Diary #3 (Actions, Action Cards and France)
Development Diary #4 (Set-up, Sequence of Play and Castile/Spain)

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Vote for EU as “Most Anticipated Historical Game of 2019” at BGG

Thanks to all of you who have already voted for us in the Historical Games Category of the Most anticipated games of 2019 on Board Game Geek. We are currently in 2nd place behind a certain game called Crusader Kings, and while we wish them all the best, we would also love to give them a good run for their money at least. The voting is happening now and until the 27th of January.

You can vote by following this link:…/20-most-anticipated-board-games…

After scrolling down to “Category: Historical” and ticking Europa Universalis: The Board Game (and any other gameyou like), you need to go to the bottom of the final category (Best of the Rest) and hit the “Vote” button. Please note that you have to have a BGG account and be logged in before you can cast your vote. If you don’t have a BGG account, please consider registering, as this can make a difference getting the word out.

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