Fellas with minds, and fellas not completely out of their minds, will eventually rout to save their own hides in the midst of combat. Dominions 6 is blessed with a manual that goes into greater detail on this mechanic, compared to previous games.
Routing fellas rush to their end of the battlefield, to try and get out as quickly as possible. In a setting without organized drill, this makes them easier targets for attackers (since they're facing away from the weapons and such), resulting in -4 Defence Skill.
Routing does not immediately dispel whatever ailments are on the poor fella. They must ride out the rest of whatever's on them, be it Poison Damage, Profuse Bleeding, or even magical ailments such as Decay. 100 rounds of these will be calculated off-screen, or however many rounds it takes for the fella to throw them off (whichever's fewer).
Even if the battle was won, fellas who rout will retreat from the province.
If their Commander DOESN'T rout in the same battle:
If their Commander DOES rout in the same battle:
The most common sort of rout happens by squad. The standard Morale roll applies here: if that's failed, the whole squad routs, though perhaps not the Commander leading them. The Morale roll for this one can only take place once per combat round (per squad).
What triggers a Morale roll of this caliber?
Once the total HP value of the whole army is under 50% of its maximum, all other triggers are ignored: as long as the army's total HP is that low, each squad is hit with the standard Morale roll each combat round. This counts those who have already retreated as still being a part of the army, but having zero HP. Once the total HP value of the whole army is under 25% of its maximum (with the same conditions), the entire army (discounting the exceptions mentioned at the top of the page) routs right away: this is known as an HP-rout.
Many varieties of troops count less towards Army HP than the average soldier:
If the rider of a Mount dies, the Mount might individually rout.
If the rider routs individually, or if the whole squad/army routs, the two ride off together. If the Mount routs individually, or if they both individually rout from the same effect, the Mount bucks the rider off. Dismounting in this fashion causes Armor-Negating damage equal to the Size difference between the two (Mount-minus-rider), complete with a DRN. Some Mounts don't cause this damage, though; all of them are Chariots.
At Turn 150, everyone with 50 Morale or lower in the attacking army routs. At Turn 170, everyone with 50 Morale or lower in the defending army routs. This is known as a turn-rout.
If there are no fellows of the correct Leadership type – fellas with Undead Leadership for Undead and Demons, fellas with Magic Leadership for Magic Beings, or fellas with regular Leadership for everyone else – then everyone who needs that Leadership type will rout unless they have 99 Morale. Illusions are a special case, requiring one of the Commanders to have either a level of Glamour magic or the Glamour Manipulator trait.
Beings with 50 Morale are Mindless. This means they don't really rout; instead, they stop fighting entirely, either dissolving or becoming completely-passive beings (depending on how you look at them). They only do this through either the lack of Leadership or the turn-rout.
On another note, beings with 30 Morale only rout due to either the lack of Leadership, the HP-rout, or the turn-rout.