A low morale in your provinces affects you in various ways. It mainly unstabilizes your empire and leads to lower productivity.
Revolts: Low morale causes revolts where people try to overthrow your government from power in that country. In the Daily European, a overthrown government will be commented for example like this: ?Rebellion in Cettinge, Cettinge is now part of Austria-Hungary?
Here Cettinge had aligned itself to Austria-Hungary after revolting against you. This is due to that countries status, geological position, and power in the region (both with morale and troops).
Revolts occur when morale is 33% or below but will be highly unsuccessful unless it hits 25% and below and has very few troops garrisoned in the province.
Production: Another fact is that a province that has 90% morale produces twice as much then a province with 30%.
Points: Morale 60% or above lets that province contribute to your points in the daily European index of power. If it hits 99% or above it gives a points bonus.
A high morale or green morale ranges from 100%-80% morale, where stability and productivity is at its highest.
Above Average morale ranges from 60%-70% whereas stability and productivity is normal. 60% and below would be threatening and 25% and under is revolt status. These percentile calculations are more or so guides to help you avoid this problem, because it will come back and haunt you.
The following things help you to avoid low moral in a province:
? avoid shortage of resources. Any shortage of any resource causes the moral of all your provinces to drop.
? raise buildings: e.g. factories, harbours and fortresses
? All provinces next to your province affect the moral. The provinces around your province should have high moral.
? the distance to your countries capital should be as short as possible. Improve infrastructure (railways, harbours) in order to decrease the travel time to the capital.
? the relations to other countries affect the moral of all the provinces in your country as well. The more countries you are at war with, the lower will the provinces moral rise
? armies in provinces DO NOT raise the moral, but in case of low moral, they can stop a revolt