关系表明了两个国家之间的态度。关系表示为-200到+200之间的数值，数值越大则关系越好，反之越差。一个国家与另一个国家的关系决定了它伤害或帮助这个国家的可能性有多大，例如与它结成军事同盟或加入反对它的战争。
如果你和某个国家的关系大于100，你不能对这个国家制造宣战理由。对列强来说，关系越高，就越容易影响这个国家。
许多决议和事件都要求两个国家之间的关系高于或低于某个值。比如，“Attack The Laagers”决议要求
Zulu和
Transvaal、
Oranje的关系都低于100。
Increasing Relations
- "Increase relations" diplomatic action (+15 relation)
- "Military Alliance" diplomatic action (+100 relation)
- Accepting a peace offer (+5 relation)
- Accepting an allies call to war (+20 relation)
- Getting military access to another country (+30 relation)
- Giving military access to another country (+10 relation)
- "Pay war subsidies" diplomatic action (+20 relation)
- "Increase Opinion" diplomatic action (+20 relation)
- Specific events and decisions
Gradual increase:
- Neighbours at Peace (+0.6 relation per year if both countries are at peace)
- Military Access (+0.3 relation per year if you get military access to another country. Note that you do not get this bonus if you give military access to another country.)
- Puppet-Master Relationship (+3 relation per year if you are a puppet or if you have a puppet)
Decreasing Relations
- "Decrease relations" diplomatic action (-25 relation)
- Declining a military alliance offer(-50 relation)
- Breaking a military alliance (-20 relation)
- Declaring a war (-50 relation)
- Declining a peace offer (-10 relation)
- Declining an allies call to war (-20 relation)
- Cancel/decline military access to your country (-10 relation)
- "Discredit" diplomatic action (-5 relation)
- "Expel Advisors" diplomatic action (-5 relation)
- "Ban Embassy" diplomatic action (-10 relation)
- "Remove from sphere" diplomatic action (-10 relation)
- "Decrease Opinion" diplomatic action (-10 relation)
- Getting caught while justifying a war (-50 relation)
- Specific events and decisions
Gradual decrease:
- Valid Casus Belli (-3.6 relation per year)