Developer Diary - Rise of Byzantium
On the 13th August 2013, EU4 was released to the public - and with it a small little event pack called “Purple Phoenix” for a country whose popularity was almost uncanny even back then. Over the ten years, this popularity did not stop but rose further and further, and now it is one of the main three focus points of King of Kings.
Welcome to today’s Development Diary which is all about the one country you guys have been looking forward to the most: Byzantium. Hardly in need of any more introduction on the country, as every single patch of EU4 has at least one video tutorial dedicated to the remnant of the Roman Empire. So without further ado, let us jump into the content we can expect for Byzantium in 1.36.
So first thing first: the setup of Byzantium. The province change has been somewhat spoiled already, but I will mention it here nonetheless to confirm it: yes, Mesambria is now part of Byzantium and it will have the Bulgarian core on it:

Another change is the adjustments on the stats of its heir, Konstantinos Palaiologos. Although the empire did eventually fall under his rule, it was not anything he could have prevented, and as such the stats he had were a bit unfair considering his experiences as the past Despot of Morea. He is now a 5/2/3!
Speaking of Morea, the area of Morea now starts with +25% Local Autonomy to represent the kinsmen of the Byzantine Emperors ruling over this part of the empire.
Another point of Byzantine adjustments is their ideas. While their +3 TotF and 3% Missionary Strength make them a strong religious country, the rest of their ideas are relatively underwhelming. As Byzantium is an end-game tag it felt kind of justified to balance their ideas a bit better out. Additionally, it is a nice reward for players who survive the early years.
These are the new ideas (Ideas with a # at the start are the modifiers that used to be there pre-1.36):
With that out of the way, let’s talk for a moment about the intentions for Byzantium. I mentioned in the Persia Development Diary that countries that receive content tend to become a lot easier than they used to be, hence Ardabil received explicitly nothing that could trivialize their early game.
Byzantium is another candidate where we explicitly want it to be a fight for survival. Because of that, the Byzantines will now start with 4 privileges which are more curses than blessings to you:
Note: That privilege increases the starting opinion of the Papal State of you by 125. More to it later.
Note: The Morale Reduction is only present if you have King of Kings active as the mission tree will give you Land Morale modifiers over the course of the campaign to counteract this privilege.

All of the privileges with the exception of 'Reliance on Republics' can be removed through decisions. Both the starting privileges and the decisions are part of the 1.36 update.
Additionally to the penalties, the privileges also cause certain events to happen to your country. Our first example is the Union of Churches. Roughly 3 months into the game you get greeted with the following event in regard to the union:

While revoking the privilege immediately would prevent the spawn of rebels further down the line, there is an argument to be made for keeping the privilege active as they can trigger the following event if you are in a defensive war against the Ottomans while having this privilege active:

I don’t want to spoil this part as this should be rather experienced in your own playthrough. But a little teaser: the second option allows for a very different religious path for the Byzantines!
Moving on, the 'Tax Exemption' privilege also fires an event that can be an early game boon with a long-term penalty.

Byzantium has been fitted with many early game events leading up to their eventual demise. While it would be lovely to showcase them all, we only have so much time. So here are a few:
Note: that event is firing for the Ottomans. The follow-up event is triggered for the Byzantines.
Also an event for the Ottomans in relation to the Byzantine content:

One final thing to mention to make the early game even more of a challenge - the starting reform for the Byzantines has been adjusted with a new penalty… and a new mechanic (more to it later):
There is nothing more Roman than falling in the back of your countrymen in time of need for a chance to seize absolute power for yourself.
Now that we have the events through, it is time to take a look at the new mission tree for the Byzantines for the upcoming DLC:

Note: with 55 missions in one playthrough, the Byzantine tree is the largest of the DLC.
First a few words about the general theme of the mission tree before going into detail: there are vastly different ideas of what is to be expected of a tree for Byzantium (a look into your local Steam Workshop is a fast way to see what I mean). Some would like to see the addition of Hellenism and a whole path revolving around it, others want a mission tree that revolves around the big “what if” questions of a modernized Byzantium that no longer tries to forge its own destiny independently from the Roman legacy.
While all of these ideas are great ones to explore, we have decided to focus on the one path which is generally the one accepted by the majority of the player base which is the ambition of restoring the Roman Empire. The goal was to keep the spirit of the Purple Phoenix mission tree and expand it with flavor so the reconquest of your empire feels like a bigger narrative than just good ol’ blobbing.
The mission tree is split into six parts:
As usual, I will start with the more obvious part which would be in that case the re-conquest missions. In this branch of the missions, you gain areas of permanent claims after another area of permanent claims. Notable within this branch is the theme of an evolving permanent modifier as a reward. Usually, you get the strong permanent modifier at the end of a mission path. Here, however, you get it early on, though in a very weak state:

This modifier will then be further modified through follow-up missions:

Finally merged into the finisher reward once you finish the conquest path of the mission tree which requests you to be the Roman Empire:

The final version of the modifier at the end of your long spree of conquest has the following bonuses:
Governing Capacity: +300
Global Missionary Strength: +2%
Yearly Prestige: +1
Morale of Armies: +10%
Morale of Navies: +10%
Stability Cost: -25%
Of course, this part of the tree has more to offer than just a growing modifier though. Here are some other great highlights of the conquest part:

Oh, while I am at it: the decision to form the Roman Empire has been adjusted.

Note: this will retroactively affect the achievement "Mehmet's Ambition" too. Also, we might add some key provinces to the decision to be part of the Empire - depending on how these changes play out.
In total, there are 475 provinces highlighted, and you will actually have to conquer MORE provinces than before. But at least you no longer have to subject yourself to the conquest of Mesopotamia anymore.
Moving on, the next part is about the walls of Constantinople:

I should talk about the elephant in the room here: yes, the Theodosian Wall is a permanent province modifier instead of a unique monument. This is a choice that has been made because we want to spread out the monuments and the Theodosian Walls would be put on a province that already has two static monuments placed on it.
Anyhow, the defensive missions are relatively easy to achieve early game which can give you some significant months to survive the Ottomans.
Now let us take a small look at the small trading missions:
Gemistos Plethon is the only, small nod to Hellenism you can expect from 1.36. For more information, I highly suggest checking out Third Odyssey.
With that out of the way, let’s continue with a more exciting part of the mission tree: the internal development and infrastructure missions:

And of course the map color in question:

It is the color of the Roman Empire.
Continuing on with the religious part of the mission tree. Due to the Council of Florence and the religious policies enacted by the last Emperor, the public trust in the Patriarch and the government has crumbled. This mission branch focuses on rebuilding that trust, limiting the rivals, and eventually bringing the schism to an end. Beginning with the trust:

While also limiting the ever stronger Muscovy ambition:

Restoring the Pentarchy:
Note: this decision is usable every 25 years.
And of course, mending the Schism:

Note: the mending will be significantly more difficult though as you must ensure that 300 provinces in Europe are Orthodox and in Orthodox hands. Fortunately, many provinces are already Orthodox. They just need a Roman hand to free themselves from the heretics.
And at last the military and administrative missions. The “Sea Fire” mission lets one already guess what it is all about. So once you finish it, your galleys get +10% combat ability for the rest of the game under the assumption that they are once again using the Liquid Fire.
Now before we continue with the branching missions, let us take a short look at a new mechanic added for Byzantium which is the Pronoia. This new subject type is available to countries with the Byzantine Autocracy, Reformed Byzantine Monarchy, the Roman Empire, and the Roman Republic government reforms.
Nations with Pronoia available will be able to convert their Vassals and Client States into a new type of subject, the Pronoia. The idea of the subject type is to provide military support during your wars. Pronoia Subjects get military bonuses and do not cost a diplomatic relation slot, but are limited by a new modifier – Number of Pronoiars.
The sources of the above include:
+1 per 100 Force Limit
+2 for “Reform the Pronoia System”

+2-4 from Byzantine Missions and up to +6 from various idea groups (namely Offensive, Aristocracy, Espionage, Quantity, and Administrative)
As for how to establish and annex these subjects and what bonuses they give, I will let those images speak for themselves:

After you ‘Retract Right to Inheritance’, the Pronoia will be annexed on their monarch’s death. We are looking forward to the “Pronoia Swarms”!
Anyway, back to the missions. Let us familiarize ourselves with the Theme System:

As you can see, The Byzantine mission tree utilizes the same Preview System as Persia does: you can choose between a standing-army build or a mercenary, feudal build:

First, let us begin with the Standing Army Build. With this rendition, you will be able to take stricter control over the Pronoia subjects that you have, opting for their quality:

There is also a mission about the Varangian Guard, allowing you to bring this nearly-extinct guard back to life, making you into the real Lord of Varangian. Lastly, a final mission that gives your troops a bit more firepower while also making them cheaper by granting them +10% Land Fire Damage and -10% Land Maintenance Modifier.
The other branch focuses on building a military based on mercenaries and Pronoiar. The missions here will allow you to focus on the quantity aspect, while also providing bonuses to Mercenaries:

The final mission here gives an additional +50% Mercenary Manpower and +5% Mercenary Discipline.
Note: All the art is placeholder, as the new icons are currently WIP. All the numbers are also WIP and are subject to change.
That was it for this week. Thank you all for reading today’s Development Diary! My colleague PDXBigBoss will continue next week with a hefty DD on Georgia, Armenia, and the Qoyunlus!
We thought you'd enjoy a sequel to the most recent Byzantium Comic From FatherLorris:
Want to embrace your inner Purple Phoenix and talk about Byzantium with others? Join our Discord here: https://discord.gg/europauniversalisofficial
Welcome to today’s Development Diary which is all about the one country you guys have been looking forward to the most: Byzantium. Hardly in need of any more introduction on the country, as every single patch of EU4 has at least one video tutorial dedicated to the remnant of the Roman Empire. So without further ado, let us jump into the content we can expect for Byzantium in 1.36.
So first thing first: the setup of Byzantium. The province change has been somewhat spoiled already, but I will mention it here nonetheless to confirm it: yes, Mesambria is now part of Byzantium and it will have the Bulgarian core on it:

Another change is the adjustments on the stats of its heir, Konstantinos Palaiologos. Although the empire did eventually fall under his rule, it was not anything he could have prevented, and as such the stats he had were a bit unfair considering his experiences as the past Despot of Morea. He is now a 5/2/3!
Speaking of Morea, the area of Morea now starts with +25% Local Autonomy to represent the kinsmen of the Byzantine Emperors ruling over this part of the empire.
Another point of Byzantine adjustments is their ideas. While their +3 TotF and 3% Missionary Strength make them a strong religious country, the rest of their ideas are relatively underwhelming. As Byzantium is an end-game tag it felt kind of justified to balance their ideas a bit better out. Additionally, it is a nice reward for players who survive the early years.
These are the new ideas (Ideas with a # at the start are the modifiers that used to be there pre-1.36):
BYZ_ideas = {
start = {
advisor_cost = -0.10
improve_relation_modifier = 0.2
#tolerance_own = 3
}
bonus = {
tolerance_own = 3
#prestige = 1
}
trigger = {
tag = BYZ
}
free = yes
repopulation_of_countryside = {
global_trade_goods_size_modifier = 0.1
#merc_maintenance_modifier = -0.15
}
byz_roman_empire = {
core_creation = -0.25
#global_manpower_modifier = 0.1
#global_trade_goods_size_modifier = 0.05
}
ecumenical_patriarch = {
global_missionary_strength = 0.03
yearly_patriarch_authority = 0.003
#global_tax_modifier = 0.1
}
byz_corpus_iuris_civilis = { #Replaces byz_admin_power for Purple Phoenix events
reform_progress_growth = 0.2
#stability_cost_modifier = -0.1
}
byz_protect_the_frontiers = {
defensiveness = 0.15
#global_trade_power = 0.1
}
byz_strategikon = {
discipline = 0.05
}
new_imperial_army = {
global_manpower_modifier = 0.15
#global_missionary_strength = 0.03
}
}With that out of the way, let’s talk for a moment about the intentions for Byzantium. I mentioned in the Persia Development Diary that countries that receive content tend to become a lot easier than they used to be, hence Ardabil received explicitly nothing that could trivialize their early game.
Byzantium is another candidate where we explicitly want it to be a fight for survival. Because of that, the Byzantines will now start with 4 privileges which are more curses than blessings to you:
Note: That privilege increases the starting opinion of the Papal State of you by 125. More to it later.
Note: The Morale Reduction is only present if you have King of Kings active as the mission tree will give you Land Morale modifiers over the course of the campaign to counteract this privilege.

All of the privileges with the exception of 'Reliance on Republics' can be removed through decisions. Both the starting privileges and the decisions are part of the 1.36 update.
Additionally to the penalties, the privileges also cause certain events to happen to your country. Our first example is the Union of Churches. Roughly 3 months into the game you get greeted with the following event in regard to the union:

While revoking the privilege immediately would prevent the spawn of rebels further down the line, there is an argument to be made for keeping the privilege active as they can trigger the following event if you are in a defensive war against the Ottomans while having this privilege active:

I don’t want to spoil this part as this should be rather experienced in your own playthrough. But a little teaser: the second option allows for a very different religious path for the Byzantines!
Moving on, the 'Tax Exemption' privilege also fires an event that can be an early game boon with a long-term penalty.

Byzantium has been fitted with many early game events leading up to their eventual demise. While it would be lovely to showcase them all, we only have so much time. So here are a few:
Note: that event is firing for the Ottomans. The follow-up event is triggered for the Byzantines.
Also an event for the Ottomans in relation to the Byzantine content:

One final thing to mention to make the early game even more of a challenge - the starting reform for the Byzantines has been adjusted with a new penalty… and a new mechanic (more to it later):
There is nothing more Roman than falling in the back of your countrymen in time of need for a chance to seize absolute power for yourself.Now that we have the events through, it is time to take a look at the new mission tree for the Byzantines for the upcoming DLC:

Note: with 55 missions in one playthrough, the Byzantine tree is the largest of the DLC.
First a few words about the general theme of the mission tree before going into detail: there are vastly different ideas of what is to be expected of a tree for Byzantium (a look into your local Steam Workshop is a fast way to see what I mean). Some would like to see the addition of Hellenism and a whole path revolving around it, others want a mission tree that revolves around the big “what if” questions of a modernized Byzantium that no longer tries to forge its own destiny independently from the Roman legacy.
While all of these ideas are great ones to explore, we have decided to focus on the one path which is generally the one accepted by the majority of the player base which is the ambition of restoring the Roman Empire. The goal was to keep the spirit of the Purple Phoenix mission tree and expand it with flavor so the reconquest of your empire feels like a bigger narrative than just good ol’ blobbing.
The mission tree is split into six parts:
- A small defensive part with three missions revolving around reinforcing the Theodosian Walls and constructing the Hexamilion Wall
- A large conquest part starting from “The Impending Doom”
- A small trade part of the two missions “Peloponnesian Renaissance” and “Monemvasian Merchants”
- An internal infrastructure part starting from “A Tarnished State” and “Promote the Emporoi”
- A part about the military and administrative aspects of the Empire
- And finally the religious part
As usual, I will start with the more obvious part which would be in that case the re-conquest missions. In this branch of the missions, you gain areas of permanent claims after another area of permanent claims. Notable within this branch is the theme of an evolving permanent modifier as a reward. Usually, you get the strong permanent modifier at the end of a mission path. Here, however, you get it early on, though in a very weak state:

This modifier will then be further modified through follow-up missions:

Finally merged into the finisher reward once you finish the conquest path of the mission tree which requests you to be the Roman Empire:

The final version of the modifier at the end of your long spree of conquest has the following bonuses:
Governing Capacity: +300
Global Missionary Strength: +2%
Yearly Prestige: +1
Morale of Armies: +10%
Morale of Navies: +10%
Stability Cost: -25%
Of course, this part of the tree has more to offer than just a growing modifier though. Here are some other great highlights of the conquest part:

Oh, while I am at it: the decision to form the Roman Empire has been adjusted.

Note: this will retroactively affect the achievement "Mehmet's Ambition" too. Also, we might add some key provinces to the decision to be part of the Empire - depending on how these changes play out.
In total, there are 475 provinces highlighted, and you will actually have to conquer MORE provinces than before. But at least you no longer have to subject yourself to the conquest of Mesopotamia anymore.Moving on, the next part is about the walls of Constantinople:

I should talk about the elephant in the room here: yes, the Theodosian Wall is a permanent province modifier instead of a unique monument. This is a choice that has been made because we want to spread out the monuments and the Theodosian Walls would be put on a province that already has two static monuments placed on it.
Anyhow, the defensive missions are relatively easy to achieve early game which can give you some significant months to survive the Ottomans.
Now let us take a small look at the small trading missions:
Gemistos Plethon is the only, small nod to Hellenism you can expect from 1.36. For more information, I highly suggest checking out Third Odyssey.With that out of the way, let’s continue with a more exciting part of the mission tree: the internal development and infrastructure missions:

And of course the map color in question:

It is the color of the Roman Empire.
Continuing on with the religious part of the mission tree. Due to the Council of Florence and the religious policies enacted by the last Emperor, the public trust in the Patriarch and the government has crumbled. This mission branch focuses on rebuilding that trust, limiting the rivals, and eventually bringing the schism to an end. Beginning with the trust:

While also limiting the ever stronger Muscovy ambition:

Restoring the Pentarchy:
Note: this decision is usable every 25 years.And of course, mending the Schism:

Note: the mending will be significantly more difficult though as you must ensure that 300 provinces in Europe are Orthodox and in Orthodox hands. Fortunately, many provinces are already Orthodox. They just need a Roman hand to free themselves from the heretics.
And at last the military and administrative missions. The “Sea Fire” mission lets one already guess what it is all about. So once you finish it, your galleys get +10% combat ability for the rest of the game under the assumption that they are once again using the Liquid Fire.
Now before we continue with the branching missions, let us take a short look at a new mechanic added for Byzantium which is the Pronoia. This new subject type is available to countries with the Byzantine Autocracy, Reformed Byzantine Monarchy, the Roman Empire, and the Roman Republic government reforms.
Nations with Pronoia available will be able to convert their Vassals and Client States into a new type of subject, the Pronoia. The idea of the subject type is to provide military support during your wars. Pronoia Subjects get military bonuses and do not cost a diplomatic relation slot, but are limited by a new modifier – Number of Pronoiars.
The sources of the above include:
+1 per 100 Force Limit
+2 for “Reform the Pronoia System”

+2-4 from Byzantine Missions and up to +6 from various idea groups (namely Offensive, Aristocracy, Espionage, Quantity, and Administrative)
As for how to establish and annex these subjects and what bonuses they give, I will let those images speak for themselves:

After you ‘Retract Right to Inheritance’, the Pronoia will be annexed on their monarch’s death. We are looking forward to the “Pronoia Swarms”!
Anyway, back to the missions. Let us familiarize ourselves with the Theme System:

As you can see, The Byzantine mission tree utilizes the same Preview System as Persia does: you can choose between a standing-army build or a mercenary, feudal build:

First, let us begin with the Standing Army Build. With this rendition, you will be able to take stricter control over the Pronoia subjects that you have, opting for their quality:

There is also a mission about the Varangian Guard, allowing you to bring this nearly-extinct guard back to life, making you into the real Lord of Varangian. Lastly, a final mission that gives your troops a bit more firepower while also making them cheaper by granting them +10% Land Fire Damage and -10% Land Maintenance Modifier.
The other branch focuses on building a military based on mercenaries and Pronoiar. The missions here will allow you to focus on the quantity aspect, while also providing bonuses to Mercenaries:

The final mission here gives an additional +50% Mercenary Manpower and +5% Mercenary Discipline.
Note: All the art is placeholder, as the new icons are currently WIP. All the numbers are also WIP and are subject to change.
That was it for this week. Thank you all for reading today’s Development Diary! My colleague PDXBigBoss will continue next week with a hefty DD on Georgia, Armenia, and the Qoyunlus!
We thought you'd enjoy a sequel to the most recent Byzantium Comic From FatherLorris:

Want to embrace your inner Purple Phoenix and talk about Byzantium with others? Join our Discord here: https://discord.gg/europauniversalisofficial

Note; your choice in this event will impact the reward for “The Northern Territories” mission! The first option will release a rebellious Syrian subject whilst the second will severely increase autonomy and unrest in Syrian provinces
Note: Keep in mind that ALL art is WIP in this Developer Diary!



Note; The other option here will grant you some permanent power projection (+15) and give you the option to move your capital to Europe (wink wink, Trade Company enthusiasts).



Note; Numbers are far from final, your feedback is appreciated!
Note; Should you complete this mission outside of the Age of Reformation, you will receive a different reward!
Note; Opting to integrate Ethiopian administration via the first option, will enable several flavor events over the course of the game (Zara Yakob as an advisor in your court, etc.) among other rewards!
Note: The modifiers are not final, feel free to leave feedback! The idea is for these units to become the backbone of your army. Not as powerful and few in numbers as the Hussars and not as stacked as the Janissaries.

Note; I had this idea while writing the DD that instead of yearly innovativeness, this reform would grant yearly army and/or naval tradition from certain advisors. I have a feeling it would fit better than yearly innovativeness. Let me know what you think!
Note; The Mamluks will have 5 new government reforms ranging from military to economic themes.
Note; A capital and a reward fitting of a prestigious nation.
Note; the Burghers are set to play a very important role within your nation’s administration. Numbers are not final!

Note; The other option grants +1 Production Development as well as stronger Estuaries and ports across the Delta’s Mediterranean coast.
Note; Yes, cloves. The requirements for this mission potentially involve a new estate privilege ‘Fund the Karimi Merchants which grants Trade Efficiency and Merchant Trade Power at the expense of National Tax and Crown land:

Note; As with the Grand Hajj, you can only have 4 such relationships with other countries at the same time, and only once per ruler’s lifetime. Hajj would grant piety and better school relations, allowing you to more easily host their scholars without depending on high-influence estate privileges and Exporting Grain would grant your allies Development Cost, Unrest and in return you would gain Mercantilism. Both actions would also improve relations.


Note to ourselves; We should rename Holy Orders to Local Organizations.
Note; The first option will allow all our administrative advisors to generate -1% idea cost reduction per level and construct a University in our capital. The second option will generate 0.25% crown land per mosque built (subtracted when they are demolished).

Note; Art is WIP
Note; Westernizing each level will change the red X to a green ✓ to keep track of your current level!

[Note: All the screenshots shown in the DD are a work in progress, as usual!]
Twice as expensive as normal orders, but it comes with one additional Base Manpower too.


Note: missing in the picture is the access to the Tribes Estate which you gain access to in the previous mission.
Note: The money gain in this particular image is lower than it will ever be due to me having this event fired via console commands without actually owning any low autonomy Cloth, Silk or Dyes provinces. The second option gives 5 years of production, the third option gives 2 years. As with everything here, all numbers are still WIP.
Note: We are aware of the tooltipping issue that says “-100% cheaper”. What is actually meant is that the advisor is 100% more expensive than a normal one. Also, once selected the advisor is immediately hired. If you fire him and rehire him you will not be able to get the modifier again.
Note: all the icons are still WIP.
Note: Personally, I am not quite happy with their identity yet, and I am grateful to hear feedback to make them feel more unique as a special unit.
Note: They are currently called Ghulams internally, but what we actually mean are Ghilman - the plural of the Ghulam. This will be fixed soon. (Yay, a lot of ID fixes to do, that’s what ‘Under Development’ truly means to be!). But for the sake of consistency, we will call them by their singular which is Ghulam.




Note: This screenshot is a bit older. The branching missions within other branching missions are replaced by the ability to pick your branch the moment where you have the choice between Islam and Zoroastrianism.
Note: Again, art is very much WIP.



Neigh, art is not final!
Note: Of course there is a decision which cancels the art promotion in case you need that Monthly Administrative Power more.








Note: Of course there are decisions which restore the old name / color.



[Beyond the Cape Mod Image]
[Portugal going around Africa without exploring New World]
[Columbus event 1]
[Columbus event 2]
[Quest for the New World event]
[Slavers privileges]
[settler pool decision]
[El Dorado]
[Fountain of Youth]
[Castile Civil War initial decision between Joanna and Isabella]
[Portuguese Unique Units]
[Venetian Unique Unit]
[Portugal missions]

[Order of Christ]
[Portugal government]
[Feitoria event]
[Overextended Empire disaster]




