Grand Strategy
The second you leave your starting city, you are alone, with no friends except the merchant you (hopefully) agreed to help. Now, from this meagre start, raising an army to take over Calradia seems a daunting (if not impossible) task. At present, there are only two important things required to build the army of your enemy's nightmares: patience and gold (see building your finances), which also reflect the three (practical) directions your army may go: quality or quantity, or a synthesis of the two.
Quantity
The optimal option to go with when starting is quantity as it is most important in the early game. Quantity involves going to many villages and simply hiring peasants or the equivalent that serve as cannon fodder and to scare away bandits. For this strategy to be effective later you will need to invest in your leadership skill, otherwise you will soon find quantity becoming obselete as the lord's parties you will face as vassal are not so easily scared away. This brings us to quality, which is the method recommended for mid game.
Quality
Quality revolves around gathering a small but experienced band of soldiers to fight your battles. The upsides are fewer casualties and hence better odds of success, however the downsides are higher cost and more battles as your group will not be big enough to keep intimidate the larger parties. It's recommended you increase your fief prosperity and buy up land to support your armies upkeep when you are in a war. (Only use moneylenders when you are 200% certain that you can pay it back in time, as failing to do so not only decreases your reputation with that town (which will increase prices)) but will raise the interest rate for future loans.
Quantity of Quality
Late game (meaning when you are a higher level than 25 and you have a weekly income of at least 3000 denars) if you invested in your leadership skill then gathering a large army of 100+ experienced soldiers is probably the best choice as the battles will become too hard for your small band, and bandit and lord group sizes will scale to your army of peasants, meaning it will become nigh impossible to win any battle even with auto-calculate. This is not to mention sieges.
Paying For Troops
While many players only build armies when they are sure they can pay for it via feifs or land owing, one must never forget the battle loot, prisoner sales, and enterprises. While all these are sources of income, an investment in a velvet plant will allow a player to add on 3 - 4 elite units, or up to 20 cannon fodder units. Battle loot, (With the introduction of the loot chance) can (but not always) give you insane amounts of money, so hunting down a few bandits here and there will always help pay wages. Battle loot can be increasingly more valuable when a player has a good relation with a town. The higher the relation, the more loot can be sold for, and the cheaper items are. Having a blunt weapon, or troops that do, can also help. A group of well trained blunt weapon experts against some sea raiders can result in as many as 20 prisoners, which do sell very well to a ransom broker. Last but not least, are area games and the tournaments at towns. Fighting in a tournament also gives you the chance to increase the relationship of a lord, in which case will allow the lord (after around 20 relationship) to follow you. Further increasing the ability to fight larger battles with better loot. More money, better troops. Better troops, more money.
Selling armor from some forest bandits.
Winning a battle also gives a nice little boost on money.
Tips
- Buying land in a prosperous, well defended coastal town (ala Praven, Tihr) will allow you to upkeep your early, mid and late game armies with ease, and is often more dependable than fiefs or enterprises. Take advantage of poor towns to buy up land before it rises in price again.
- Tactics wise, you can often do well with your small band of experienced troops, and save money by neglecting cavalry and rather investing in archers and infantry to prop up on a hill (infantry on the slope, archers up top).
- When fielding a purely quality or quantity force, try to reinforce other lords armies or vice versa to prevent yourself from being overwhelmed by larger professional armies.