Allegiance is the measure of loyalty of a planet to an empire. In terms of game mechanics, allegiance determines an empire's economy.
The allegiance value of a planet is determined by two factors: the location of the controlling empire's capital planet and culture.
Capital planets have 100% allegiance (irrespective of culture upgrades). Every planet one phase line away will have 90% max allegiance. Every planet two phase lines away will have 80% max allegiance. This pattern continues until allegiance reaches 35% and the only thing that can drop allegiance below that is enemy culture.
Both friendly (domestic or allied) and enemy culture affects allegiance. A dominant friendly culture will increase a planet's maximum allegiance by 10%, and a dominant enemy culture will decrease a planet's allegiance by 10%.
Changing Allegiance Edit
With certain research (Allure of the Unity for Advent in Entrenchment) it is possible to have allegiance above 110% for your capital planet (up to 120%). The allure of the Unity gives you a 10% bonus maximum allegiance for all planets. The highest possible is 150% allegiance if you have a Starbase in your capital planet's gravity well and the Starbase is equipped with Induced Reverence (increases maximum allegiance by 15/30%). So it is possible for Advent players to have their farthest colonies to have 45% maximum allegiance (with culture) or 75% maximum allegiance with a Starbase with 2/2 Induced Reverence, which gives Advent players a big boost for the late game economy in huge multi-system maps.
Effects of allegiance Edit
Planets with higher allegiance are more productive, generating more credit, metal, and crystal income. For example, a capital planet with an allegiance of 100% will contribute 100% credit, metal, and crystal income to an empire, while a capital planet with 110% allegiance will contribute 110% income, an increase of 10%.
If the allegiance of a colony falls to zero, a revolt will occur and the colony will be lost to the empire it belonged to. The planet will become neutral and vulnerable to colonization by enemy empires. If the planet is under the influence of enemy culture it cannot be colonized by you or any allies until the enemies culture is repelled.