Core

From EU3 Wiki

A core province is a province that is considered a rightful part of your realm. Unfortunately, several nations can have a given province as their core, often resulting in wars over the ownership.

Contents 1 Effects of cores 2 How to spot a core 3 How to gain a core 4 How to lose a core

Effects of cores

Having cores on provinces outside your realm will give you a casus belli on the country owning the province. Obviously this also means that other countries with cores on provinces in your realm will have a casus belli on you. Core provinces generates an extra 90% of the direct tax paid at the end of each year. Non-core provinces will have a nationalism effect for 30 years after their capture. This effect increases revolt risk by 3%.

How to spot a core

You can check which countries have core claims on a province by clicking the province and checking the bottom-right part of the province interface. Little shields show the countries with a core claim on this province. Often there will be only one country with a core and thus only one shield, but it can be more. In example: the province Béarn in southern France is considered a core of Foix, France, and Armagnac in 1453.

Another way of checking cores is through the diplomatic map mode; the map will show the selected country as bright green and cores outside the country's borders with bright green stripes. Note that this only shows cores not currently part of the selected realm, it does not show whether a province inside the realm is actually a core province.

How to gain a core

Typically the provinces that a country own at startup is also its cores, while some nations have additional claims outside their borders. During the game additional cores can be gained, either through events, by occupying a province continuously for 25 years, by holding a province 50 years after annexation (IN), or by the spy action Fabricate Claims (EU3 and NA). Since Heir to the Throne the Holy Roman Emperor can also initiate a vote through a decision to enact "Renovatio Imperii Romanorum". If the vote succeds, it will lead to the whole Holy Roman empire being unified as a single nation under the Emperor with cores in all provinces.

How to lose a core

A country can lose a core claim on a province that is outside it's borders. This can happen as part of a peace negotiation following a lost war, or automatically if the country has not tried to capture (going to war with the country that controls the province or having them as a vassal) the province for 50 years. You will however not lose cores on same culture provinces outside of our realm this way.