Summary
There is a hierarchy to everything inCrusader Kings 3, a height to which you can always ascend. Yet the higher you go, the more you have beneath you that must be handled, and that is no simple task. This applies to more than just your vassals, but the land itself, split into Kingdoms, Duchies, Counties, and Baronies.
Duchies comprise a handful of Counties, with a single one of those counties able to hold a Duchy Building. Only one of these can be constructed per Duchy, so it important to be mindful. This same restriction also means they are incredibly powerful buildings, and ones you should hope to capitalise on.
Some Duchies have unique buildings, as well as some that can only be used by certain faiths and such. This list focuses on the general Duchy Buildings available to everyone.
8Jousting Grounds
The Jousting Grounds serve a dual purpose. First off, they strengthen the stats of all of your Cavalry units stationed there. They also give a general reduction to the maintenance you have to pay on your Men-at-Arms, to a total of up to 10%. However, they also reduce the cost for Jousts and Horse races of Grand Tournaments hosted here.
There is no denying the incredible use for this, especially if you are focused on cavalry units in your army, though it is not quite as useful for a more diverse army, especially with many of its benefits also available from other Duchy Buildings.
7Royal Reserves
The Royal Reserves have little to do with expanding your army and its strength like many other Duchy Buildings. Instead, it focuses on increasing your personal wealth, as well as that of your entire realm. By sectioning off land for the royalty, you can effectively control its development and extract further wealth from anyone trespassing on those lands.
The Royal Reserves gives a dramatic development growth bonus to the Duchy it is part of, with up to a 30% bonus when fully upgraded. This is on top of a large income tax increase, plus popular opinion increases for you as well. It also increases Hunt Success Chance, if all the extra wealth wasn’t enough.
6Leisure Palaces
Leisure Palaces are all about keeping the peace at home, whether that’s with your faithful vassals, or the peasantry within a Duchy. Within the Holding this is constructed, you gain a 50% discount on any feasts hosted here, as well as lose more stress and gain more renown from Grand Weddings.
That’s not all though. Control increases dramatically in this Duchy, while the holder, which is ideally you, will gain extra prestige just for owning it, increased stress loss, and ahigher success chance in all of your schemes, both hostile and personal. Sometimes, it takes a chat in a very lavish castle to advance your regime.
5Royal Armories
Royal Armories are slow to get going initially, but prove immensely powerful once they get upgraded all the way to the top. They are through-and-through about upgrading the strength of your military, though also reduce the cost of Grand Tournaments as well. This is great for when you have a more diverse army.
This Duchy Building increases the Damage and Toughness of your Men-at-Arms stationed here by a maximum of 25%, while reducing the maintenance of your entire army by 10% at most. However, it bolsters the size of the levies provided from this Duchy as well by up to 40% to buff out your army for next to no gold increase.
4Siege Works
As time goes on and the forts in each holding get stronger and stronger, an unbeatable army will mean less. You can trounce any army you come across, but won’t be able to pierce a heavily fortified wall. That’s where the Siege Works Duchy Building comes into play. Walls mean nothing to a powerful bombard, after all.
The SIege Works increase the Toughness and Effectiveness of your Siege weapons by up to +15 and +40% respectively. It also makes it cheaper to maintain and create new Siege units, as well as fortifying every fort already in this duchy by up to +6. It’s great offensively and defensively.
3Tax Offices
An empire runs on many thingsin Crusader Kings 3, and while it’s unlikely to last forever, a healthy income is sure to give it a bit more life. Money makes the world go around, after all. And the Tax Offices Duchy Building will make those taxes your vassals are already paying all the more lucrative.
Tax Offices are simple, increasing the modifier of the taxes you receive in the Duchy this is constructed. It does not by default give you any extra tax however, so it must be constructed in a Duchy that already has high income. At its highest level, this will increase the gold you receive in the entire Duchy by up to 30%.
2Marches
While most other Duchy Buildings have focused onincreasing your incomeor offensive capabilities, Marches are instead all about your defensive options. Its benefits are exclusively for the Duchy it is constructed in, but they are plentiful, giving your realm some incredible defenses during war, and even some benefits when at peace.
Marches increase the supply limit within the Duchy, letting you bring massive armies here without fear of attrition, while also increasing the size of your garrisons, fort level and the length of time it takes to raid in this Duchy. Your Levies reinforce faster, too, and you get a bonus when defending. And even outside of war, you get a percentage boost to your taxes in this Duchy from any Hills, Mountains, or Desert Mountains terrain.
1Military Academies
Training an effective army is sometimes the most effective option you have for both conquest and defense, and Military Academies make that a cinch. Instead of focusing on your Men-at-Arms like many other buildings, it is focused most keenly on your Knights, though comes with plenty of benefits for your army and MaA as well.
At its max, you can have up to six more knights, while their effectiveness is boosted by 75%. The size of each MaA regiment also increases by +3, while Army maintenance decreases by 5% and recruiting new ones costs 30% less. The most powerful, however, is the ability to train your knights while traveling. This can give ginormous boosts to their martial stat, making them nigh unbeatable in combat.
