System Rebellion

System Rebellion is a constant risk for a ruling House, as other noble Houses constantly seek to take advantage of a ruler's weakness and elevate themselves on the galactic stage.

Codex
"Few houses in a colony would not relish the chance of being the ruling house of that colony. Nobles scheme endlessly how to achieve such a goal and from time to time dissatisfaction with the ruling house's reign provides such an opportunity.

When a noble house rebels, houses on the colony pick the side they will support, splitting the colony's fleet accordingly. While some skirmishes on the colony will ensue, the primary struggle for dominance is still in space.

Most system rebellions are doomed to fail, since even unpopular ruling houses usually have stronger relationships with houses from other colonies than the rebels.

If the rebel house is not defeated in this struggle, and manages to overthrow the previous ruling house, it is generally acknowledged as the new ruling house of the colony. By default, the colony remains a legitimate member and vassal of its faction. However, a successful rebellion on a faction's capital system will dissolve the faction."