Crusader Kings 3 gives many options beyond ruling and prospering simply by the sword's edge, yet war seems an inevitability. Whether it comes in the form of seaborne Viking raiders, bothersome peasants, or incredibly jealous younger brothers, even the greatest among Crusader Kings 3 diplomats struggle to know peace. This is no Imperator: Rome – there is no Pax Romana. Medieval realms, particularly early medieval ones, relied on fearless leaders and knights.
Fortune may favor the bold, but it favors best the bold, clever and well-prepared. So what preparations should the Crusader Kings 3 strategist consider? What attempts at cleverness will the game actually reward? Allies in Crusader Kings 3 are both consistently present and incredibly fickle. Enemies are fairly cautious: only in certain circumstances will they go suicidally into certain doom. A player can improve their IRL Martial education by understanding these forces; by knowing when and where to fight, when to stand resolute, and when to flee.
Updated May 30, 2022 by Ryan Bamsey: Crusader Kings 3 is continuously updated with new features and balance changes. As a result, we've gone over this article to make sure our tips and tricks remain useful and valid, and we've also added some new ones that reflect the new features added with the Royal Court DLC.
12 Let Them Come
It's always tempting to immediately cut loose the dogs of war. Sure, a swift offensive is sometimes the perfect thing. If an enemy is engaged with other forces, they can be caught at a moment of weakness; for instance, if they have distant allies to call into the fray, the player's army may arrive before their reinforcements.
However, there's more to consider. Namely: fighting on a friendly castle grants a healthy bonus. Travel in foreign territories causes loss of supply, which can turn a wild goose chase into a debacle. Armies, particularly small ones, can also be devastated by attrition in hostile territory. These problems of attrition and supply can be avoided by leaping right into offensive siege warfare, but this puts the player in a poor position for battle. Why not first crush the enemy army using a home turf advantage?
11 Choose The Ground Carefully
Unpleasant surprises await those who blindly right-click on enemy forces. Mountains, hills, taiga, forests, wetlands, and jungles offer strong defensive positions, while also reducing Combat Width – giving smaller armies a better chance of victory. Certain men-at-arms units will perform better or worse based on the terrain, as well.
Only the reckless cross water without consideration. Armies can't fight effectively over rivers or straits unless you have the Strategist trait, and disembarking from naval transports leaves forces with some time before they're fully reorganized and back to full effectiveness. Take advantage of water for defense and avoid it when attacking.
10 Prioritize Capitals
Not only are capital regions the gleaming jewels of their realms, but they're where ruling families (and their many lovers) tend to reside. Go ahead and make things personal. Enemy rulers hate it when players capture their heir, and they'll give in to any demands when they're captured themselves. Unsurprisingly, AI will go to some extreme lengths to defend their capital, including occasional risky attacks against besiegers (also, against raiding armies).
Capital vulnerability is a classic double-edged sword. It's easy to be blasé about losing territory, but it becomes far more difficult when an exposed capital has been lost and cherished family members are in irons. And if the player character themself is captured, the war is immediately lost.
While going for capital cities is a valid tactic, be aware that traveling deep into enemy territory that you haven't already occupied will cause you some terrible attrition and supply drain, losing you soldiers and manpower. It may take longer to capture all the provinces that lead towards a capital, but it's safer.
9 But Also Prioritize The War Target
Heading straight for the capital of your enemy will let you hamper what is likely one of their strongest counties, but don't forget that many wars - specifically those that involve pressing claims - will have different war targets.
While you control the war target, you'll receive a ticking warscore buff. Not controlling it will reduce your warscore. Naturally, it's a very good idea to go after the war target as soon as you can. You can view the war target by opening up the war overview menu - the war's name should give you a clue!
8 Don't Undervalue Mercenaries
In Crusader Kings 3, money is power and quantity often wins over quality. It's a very good idea to keep a large stash of gold available in order to hire mercenaries, who make themselves useful very quickly when war breaks out.
When war forces you to fight on multiple fronts, it can be very handy to just summon up a huge army of mercenary soldiers to distract foes from your main attachment. They can be expensive, but they are absolutely worth their weight in gold.
7 Travel Divided; Fight United
As previously mentioned, supply-induced losses will chew an army up. Avoid them by staying under the supply limit of provinces, which is done by traveling with armies of relatively small size. Split and, later, regroup forces with the 'F' and 'G' keys.
Of course, small armies must be watched carefully, as they can be picked off without reinforcement from their colleagues. The presence of nearby armies should deter attackers but isn't to be relied on. Outflanking the enemy is an option for divided armies, but drawing back together is certainly safer.
6 Trust No Allies
Too often, calling an ally to war is a set-up for disappointment. Crusader Kings 3's issue isn't allies failing to come to player's assistance at all, but that they can't be directly dictated to. This means allied armies will not join what they perceive to be a losing fight, leaving a player who simply wanted to test fate utterly doomed. Even when they are trying to join battles, allies often arrive late because of inconsistent pathfinding and reluctance to be in the same region as player armies. It's a real shame as allied help is integral to surviving difficult starting positions.
Players should consider directing their armies all the way to an end goal rather than simply the next region (shift-clicking to make a selective path). Allied AI tends to better understand when the player's army is aimed right at an enemy target.
5 Give 'Em Double Trouble
What is the very last thing a foreign ruler wants while they're engaged in a desperate war? A no-longer-neutral player's armies knocking on their back door. So yes, strike foes while they're at their weakest: when their existing war is going poorly.
However, take caution. It's dangerous to fight over the same parcel of land as a fellow attacking ruler. Even when the two aggressors have different objectives, in Crusader Kings 3, the enemy of your enemy is not necessarily your friend. Players may support the enemies of enemies in battle, but may also find their gains under threat from those forces.
4 Stay Well-Equipped
Introduced with the Royal Court DLC were artifacts, items that you can equip to your current player character to give them various bonuses. Among these are various accessories, clothing items, and most relevantly, weapons.
In Crusader Kings 3, weapons will often provide very powerful buffs to your ability in war, sometimes improving specific unit types or giving a buff to your Martial score. Accrue a vast inventory of weapons and you can pick and choose the right arm for the job at hand.
3 The Strategy Of The Central Position
Imagine this situation: two enemy armies, each somewhat weaker than the player's army, but combined nearly twice as strong. The objectives are to prevent these armies from linking up and to crush them individually.
The player should divide their army just before battle: one tiny force to delay the stronger of the enemy armies, and a crushing force to overpower the other. If timed well (and with luck), the strong enemy army will be prevented from coming to the aid of the weaker one. This probably means sacrificing the delaying army (unless it managed to bait the enemy and flee), so hopefully, it was made of swift, casualty-resistant horsemen or levies (which are easy to drum up).
2 Watch For Talent
For starters, good commanders can be attracted through matrilineal marriages. While a super talented leader is an invaluable hubby, bear in mind that having a range of commander traits is also quite useful. Once this range is acquired, don't forget to swap out commanders based on the strategic situation.
The Marshal's "Train Commanders" task is one of his best contributions to military power. Be aware that this makes constant territory acquisition risky, as the Marshal must be devoted to increasing country control. For expansionist players, this can result in being stuck sending poor commanders against well-trained AI leaders.
1 Break The Game With Men-At-Arms
To share this knowledge seems almost immoral. Therefore, sharing it is the most Crusader Kings thing to do. The mid and late-game is a carefree jaunt if you simply choose one military building, upgrade it to the highest level in every holding, and train only the one or two men-at-arms types that the building benefits. Meanwhile, the AI will not be effectively upgrading. The counter system will become irrelevant under not only the weight of bonuses but the fact that having at least double the kind of unit countered outweighs the countering unit.
Pikemen are a good choice for this strategy, as are archers, who are a very strong counter in the early game and upgrade well later on. Light cavalry, especially Sahel cavalry, are very good in desert and steppe regions.
So, there it is. Having a few siege weapons is still a smart bet, but other than that, repetition seems to be mastery.