Keeping your armies in fighting shape is a key to victory in Total War: Three Kingdoms. You need to be able to maximize your ability for an army that has just taken losses to recover, and quickly get ready for the next fight.
Knowing the factors that will impact your ability to replenish your army is very important.
How Army Replenishment and Population Work
Each Commandery will offer different bonuses to your Replenishment based on the population. If you check the population button in the bottom left corner of the screen when looking at a Commandery, you can see the various bonuses that your population will give you. These include bonuses to income, construction time and a local replenishment bonus for your army.
You will also see how many people currently live in the Commandery and the maximum population for the area. The closer the population is to the max, the larger the bonus you will get to your Replenishment in the area.
This bonus to Replenishment will be applied when your army is recovering from loses, or recruiting new units.
To increase the population of an area, and the relevant bonuses you get from that population, you need to construct new buildings in the Land Development chain. The Land Development chain provides buildings that produce crops, or trading, both of which will support population growth in the area.
It is very important to have buildings that can produce food, not just to grow your population, but also to increase your food reserves for your armies’ military supplies. When your faction-wide food balance is positive, your reserves are filled, but when your faction-wide food reserves are negative, they will deplete.
As such, it is important to always make sure that you are building the right buildings to support population growth, especially if you are expanding by taking over new settlements, towns, and cities.