Army

An army represents a group of armed soldiers fighting on behalf of a nation, composed of individual cohorts and represented by a pawn on the map that can be moved around on its own. War is waged primarily with armies, whose main role is to occupy and siege enemy territories and fight other armies to deny them the ability to occupy and pillage a country's own lands.

Generally, armies are raised from a country's integrated culture population and divided into two main types. At game start, each country may raise soldiers from their integrated culture pops to fight as levies, which while can be quite large relative to a country's population are by their nature hard to organize and cannot be maintained for too long without stressing the social fabric of the nation. As a country expands and develops, they may transition to be able to recruit legions, which while more expensive are permanent, professional military forces whose organization and composition can be more carefully controlled. If a country needs more men than can be raised from its population and is wealthy enough to afford it, mercenaries offer a third option, if somewhat more fickle.

Armies are typically led by a commander who, while subservient to the government, ultimately is the person who exerts direct control over the army. A well-led army can be highly effective in battle and punch well above its weight to turn the tide of a war, but the command of an army is also a powerful position that has a significant impact on the loyalty of its holder. A disloyal commander will refuse any orders from above and follow their own objectives that may well not be that of the country as a whole, and may at some point decide to side against the government - along with all the troops under their command - in the event of a civil war.

Name

All armies have a name that allows for easy identification, which by default is generally based on the type of the army and the region that it was raised from. Any owned army, except for mercenaries, can be renamed at any time by double-clicking on the unit name on the top of the unit panel.

Every legion also has a name and can be renamed to the player's liking by double clicking on its name in the Legion tab of the military panel. The names of every army in the legion will by default include the name of its legion, and if the legion's name is changed, the name of the cohort will be automatically updated as well.

Army types

Levies

Levies can be raised from free (non- slave) integrated culture pops in every owned region. The strength of a region's levy, the number of pops that are actually raised in the levy, is determined by country's levy size modifier, with a base of 7.50% of eligible pops that can be raised; the size of levies can be modified by various laws, military traditions, government types, heritages, and more, and additionally always has a minimum of 4 pops that can be raised per region. Every pop that is raised becomes a single 500-man cohort, with the overall unit type composition of the levy depending on the culture that it is raised from. For every 9 cohorts that are raised, the levy will also get an additional supply train support unit.

Raising a region's levy does not cost any gold, but instead costs 0.5 war exhaustion. Levies will be raised by default in their governorship's capital, but can be raised from anywhere in their governorship by clicking the appropriate territory in the Levies mapmode. Levies can be freely split and merged back into themselves, but a levy cannot be merged with an army of a different type or a levy raised from a different region. A levy is always commanded by the governor of its region (including the ruler for levies raised from the capital region), including if a levy is split up; the region's governor will be considered the commander of all the different levy components simultaneously.

In tribal governments, levies are instead led by clan chiefs, and levies from a single region will often be split up such that each clan chief gets at least one army to take command of. Even if they were raised from the same region, levies led by different clan chiefs cannot be merged together. Tribal nations also have a significant bonus to levy size, to compensate for their generally smaller populations and the fact that they cannot raise legions.

Once raised, levies do not require any maintenance, but raised pops do not have any production which can have a significant impact on tax income, research points, and manpower production. Levies that are raised for longer than 6 months will also produce additional war exhaustion, on top of any accumulated from attrition or occupied territories. If a levy cohort is overrun or destroyed in battle, there is also a chance that its associated pop will be killed, which can make it quite damaging to lose large numbers of levies in a war. If a levy cohort's pop is lost or is no longer eligible to be raised as a levy, the cohort will no longer be able to reinforce and will slowly lose strength each month and will eventually disappear as it is no longer being supplied.

Levies can only be disbanded 4 months after they were raised, during peacetime, are not moving, and if their governor is loyal. Levies cannot be disbanded normally and must be dismissed from the Levies tab of the military screen on a governorship-wide basis. If a levy has been raised for at least 8 months, every levy cohort that is disbanded will grant 0.015 military experience for each point of cohort experience. This compensates for the fact that they cannot drill and are not meant to be raised permanently, and so tend not to accumulate much passive military experience gain. Once a levy has been disbanded, it will take between 4 and 24 months for the region's levy to be ready to be raised again, depending on the strength of the levy when it was disbanded. However, they can be instantly raised during a defensive war.

Following is a complete list of levy size modifiers.

Type	Modifier	Levy Size Modifier
Base	Base	+7.5%
	Centralization Level	+0.15% per point below 0% (up to +15% at -100%)
	Antagonist	+5%
	In Defensive War	+1%
Country rank	City State	+12%
Government	Settled Tribe	+5%
	Federated Tribe	+10%
	Migratory Tribe	+10%
Laws	Royal Guard (Monarchy)	+2.5%
	Noble Retinues (Monarchy)	+5%
	Military Service (Monarchy)	+10%
	Citizen Militia (Republic)	+5%
	Noble Elite (Republic)	+2.5%
	Provisioning Act (Republic)	+2.5%
	Servian Levy ( Roman Republic)	+5%
	Republican Levy ( Roman Republic)	+7.5%
	Punic Reforms ( Roman Republic)	+2.5%
Inventions	Auxiliary Recruitment ( Religious invention)	+2%
Military Traditions	The Honor of Service from Roman traditions	+2.5%
	The Bureaucracy of War from Indian Kingdom traditions
	Reactive Recruitment from Persian Rural traditions
	Confederations from Britannic traditions
	Call to Arms from Punic traditions
Heritages	Roman Heritage (Rome)	+2.5%
	Spartan Heritage (Sparta)
	Epirote Heritage (Epirus)
	Carthaginian Heritage (Carthage)	-2.5%
	Mauryan Decline Heritage (Maurya)

Legions

In republics and monarchies, certain military reform laws allow for the recruitment of permanent armies of professional forces called legions (tribal nations cannot recruit legions until they reform into a republic or monarchy). Where a levy consists of an assortment of units based on the culture of the pops being called into service, the troop composition of legions can be much more precisely controlled. Like levies, each legion is associated with a particular region and shares the same pool of strength, drawn from free integrated culture pops with the proportion determined by the country's levy size modifier; this means that for every cohort recruited into a legion, one less cohort can be raised from that region's levy, and the size of a region's legion is capped by the region's base levy size (not including support units). If all of a region's levy strength is used up in its legion, no levy can be raised from that region. Laws that allow for the raising of legions have a lower levy size modifier than those focused on levies, which generally leads to a choice between a larger but more disorganized levy, or a smaller but higher quality legion. Notably, engineers cannot be raised as levies and can only exist as legion subunits.

Creating a new legion costs 25 gold. Once a legion has been created, cohorts can be added to any of their units as long as it is in an owned and controlled territory. Each new cohort costs 500 manpower and a variable amount of gold per cohort depending on its type, from 8 gold for archers and light infantry to 40 gold for engineers. Once built, cohorts will be immediately added to the unit without any travel time.

Up to 4 commanders can be assigned to each legion. The main commander of a legion is known as the Legate, and will be the default commander of the main army. If a new unit is created from a legion, one of lesser commanders, called Tribunes, will take command of that unit. The command of any of a legion's units can be freely swapped between its 4 commanders (even the legate), though a character will lose 5 loyalty if their command is revoked. A legion can be split into different armies and freely merged or reorganized within the legion, but like levies legions from different regions cannot be merged together. There is no limit on the number of armies that a legion can be split into as long as there are enough cohorts to do so, but as each commander can only lead one army at a time if there are more than 4 armies in a legion, at least one of them will necessarily not have a commander.

Any units of a legion can be disbanded at any time as long as it is not in battle or in retreat, which will return 25% of the cohort's manpower back to the pool as well as removing any need for maintenance, but has an upfront gold cost of 15% of the recruitment cost, increasing to 20% for cohorts that are loyal to a character. Unlike levies, legions do not give any military experience when disbanded, but as legions are persistent units that are maintained even during peacetime and can drill to improve their cohort experience outside of battle, they generally contribute much more to passive military experience generation.

Legion maintenance

As a professional army, legions have a monthly maintenance cost, with a base value of 1/48 (around 2.08%) of its total recruitment cost (corresponding to 25% of the total recruitment cost each year). The maintenance cost is reduced to 66% of normal (1/72 or 1.38% of total recruitment cost monthly, 16.5% of total recruitment cost yearly) for cohorts that are loyal to a character, and removed entirely for units commanded by disloyal characters. Legion maintenance is then further modified by the legion maintenance cost modifier, which can be toggled in the economy tab for either higher morale or saving on expenses as well as from a large variety of other more permanent modifiers.

Distinctions

Main article: Distinction

As legions fight in wars, they may accumulate distinctions, permanent modifiers to their fighting capabilities that apply to all of their units. Distinctions are generally accumulated by a legion over time and apply to all of a legion's armies and commanders, and can give strong bonuses that will generally make a legion significantly stronger than a levy of equivalent size. A legion's important victories and defeats will also be recorded in their legion history.

Most distinctions are available only with the Heirs of Alexander DLC.

Migratory armies

Main articles: Land units#Migratory units, Tribal migration

Migratory armies are a special army type available to Migratory Tribes, composed of migrant cohorts that can be raised by uprooting the entire population of a territory. Starting a migration in a territory requires that the region not have any levies raised and costs 8 stability per territory, converting each pop in the territory into a single light infantry cohort that, like levies, do not cost any maintenance. While not very powerful and potentially quite costly as migrating entails abandoning territory and the loss of any migratory cohorts equates to the loss of a whole pop, the ability to raise units out of every pop in a territory means that even relatively small countries can raise a truly large host if they are willing to take the risks.

Migratory armies are unique in that they do not require military access to move onto or across other countries' territories, and a country can continue to exist even without owning any territories as long as it has at least migratory armies. They also have the unique unit abilities that allows them Raze Cities to gain research progress from damaging the cities of more advanced countries, as well as settle on controlled or uncolonized territories to take control of the territory and turn the migratory cohorts back into tribesmen pops.

Mercenaries

Not to be confused with mercenary states, a special subject type.

Mercenaries are soldiers willing to fight for any country in return for gold. While a significant expense that should not be taken lightly, mercenaries can play a decisive role in wars by allowing wealthy countries to augment their military forces beyond what their population and manpower can support, as well as coming with skilled commanders that can give a decisive edge in battle - as long as their employer was willing and able to pay them, and nobody else could come with a better offer.

Mercenaries are organized into individual mercenary companies, each with its own commander (that all of its cohorts are loyal to) and based from a particular territory from which it draws its culture, size, composition, and unit graphics, and stands while unhired; importantly, larger cities will typically support larger mercenary compaies. Mercenary companies appear all over the map and are typically found in major cities and other population centers; disenfranchised heirs and princely adventurers may also decide to seek fortune by forming their own mercenary companies. All mercenary companies can be viewed in the Mercenaries screen, along with their strength, composition, maintenance costs, current employer, and more. From this interface, countries can also hire and otherwise interact with mercenary companies.

Mercenaries are affected by army modifiers such as discipline, morale and damage.

Hiring Mercenaries

While unhired, all mercenary companies belong to the special Mercenaries faction, which is neutral to all countries, and will stand in their home territory waiting for a contract. They do not count towards the supply limit of the territory where they are located and will not fight other armies, in effect not interacting with anything else at all.

Any mercenary company can be hired as long as it is within diplomatic range, it is not already employed, and the country can afford the upfront cost of 100 gold, modified by the country's recruit mercenary cost modifier. It is not possible to hire only part of a mercenary company; a company must be hired all at once. Once a mercenary company is hired, it immediately comes under the control of its employer, but is not automatically moved from its base and must be moved to where the country plans to use it. Hired mercenary armies outside of a country's territory will begin in a state of exile and must be moved to controlled territory before they can used in battle. This means that hiring an army far from the conflict zone could get expensive, as maintenance is paid from the day they are hired.

Mercenary armies also start with 0 morale, so they will not be ready for battle for a number of months and should generally be hired ahead of time. Using the Unit Reorganization ability once it is in controlled territory can speed up this process, though it will be even more expensive than using on a normal army. Once no longer exiled, the mercenary army will act as any other controlled army, except for the fact that their leader cannot be removed and that they cannot be merged, split, or otherwise reorganized. In particular, mercenary armies do benefit from all military modifiers that a country has, and as they have no interest in a country's politics they will always have maximum loyalty - unless they are not paid, or get a better offer. Almost as importantly, mercenaries do not reinforce from the manpower pool - this means that they do not cost manpower to reinforce, and will always reinforce even if the country is out of manpower.

Mercenary limit

Every country has a maximum number of mercenary armies that they can hire at a time, determined by their maximum mercenary armies modifier that is increased largely through inventions and country rank. Once a country has reached or exceeded its number of maximum mercenary armies, it will be unable to recruit any more until they either raise their cap or disband one of their currently employed mercenaries (though this does not apply to bribing mercenaries employed by enemy countries). Note that each mercenary company, regardless of size or composition, counts the same amount towards the cap; this means that even after reaching the mercenary limit, a country can still increase the strength of its mercenary armies by disbanding weaker employed companies and hiring larger, stronger armies.

Mercenary maintenance

Maintaining a mercenary company is somewhat more expensive than a legion with an equivalent size and composition, with a base multiplier of 150% the normal legion maintenance cost (i.e. a 50% increase over the base maintenance cost). The maintenance cost of a mercenary company is then modified multiplicatively by the both the standard legion maintenance cost and mercenary army maintenance modifiers, which gives the following formula for each the maintenance cost of each mercenary army cohort:

${\text{Monthly Maintenance}}={\text{Base Maintenance Cost}}\cdot 1.50\cdot (1+{\text{Mercenary Army Maintenance}})\cdot (1+{\text{Legion Maintenance Cost}})$

Note that this means that if a country's mercenary army maintenance modifier is less than -34%, mercenaries will in fact be cheaper than legions.

Disbanding Mercenaries

As with most armies, a mercenary army can also be disbanded at any time, as long as it is not in battle. Disbanding mercenaries means that that the country will no longer have to pay for their maintenance has no cost, other than losing use of their commander and soldiers. A mercenary army will also be automatically disbanded if it is completely destroyed in battle.

Once disbanded, the mercenary army will again be considered available for hire, and it will begin its journey back to its home location. Once it has returned, it will slowly reinforce back to full strength.

Desertion

As a mercenary's loyalty is dependent entirely on the ability of its employer to pay them, being unable to pay hired mercenaries is problematic and can create rather dangerous situations. If a country goes into deficit and becomes unable to properly pay its mercenaries, mercenary armies will become disloyal and refuse to listen to orders or actively engage the enemy. If the deficit goes below -50, hired mercenary companies may take more drastic action; they may decide that the contract is over and desert its current employer while sacking the local territory, defect and try to find a better contract with an enemy nation, or even decide to take their payment in land and seize control of the local province.

A country can also attempt to bribe an enemy nation's hired mercenaries if they have at least 24 gold for every cohort in the mercenary company, and the mercenary company has not been bribed in the last year. The mercenary's current employer will then either have to match the offer or face the mercenary switching allegiance to their enemy. Adopting the Mercenary Benefits Civic Invention will prevent enemy countries from bribing a country's employed mercenaries.

Modifiers

The Following is a list of mercenary modifiers:

Type	Modifier	Mercenary Modifier
Inventions	Professional Sailors ( Martial Invention)	Maximum Mercenary Armies +1
	Mercenary Benefits ( Civic Invention)	Recruit Mercenary Cost -25%
	Mercenary Reliance ( Oratory Invention)	Maximum Mercenary Armies +2 Mercenary Army Maintenance -5%
	Satellite Status ( Oratory Invention)	Maximum Mercenary Armies +1
	Auxiliary Recruitment ( Religious Invention)	Maximum Mercenary Armies +1
Military Traditions	Arms for Hire (Greek Poleis traditions)	Recruit Mercenary Cost: -15%
	Deep Coffers (Greek Kingdom traditions)	Mercenary Army Maintenance: -10%
	Good Reputation (Levantine Kingdom traditions)	Mercenary Army Maintenance: -10%
	Good Reputation (Indian Tribe traditions)	Mercenary Army Maintenance: -10%
	A Hard Bargain (Punic traditions)	Mercenary Army Maintenance: -10%
	Skilled Recruiters (Punic traditions)	Mercenary Army Maintenance: -5% Recruit Mercenary Cost: -25%
Laws	Mercenary Contract Law (Monarchy)	Mercenary Army Maintenance: -10% Recruit Mercenary Cost: -25%
Office	Marshal (Monarchy)	Mercenary Army Maintenance: -1% per 1
Subject nations	Mercenary state	Mercenary Army Maintenance: -3% per mercenary state
Country rank	see country rank

Commanders

See also: Position#Army commanders

Most armies are led by a commander that organizes and leads the army at a tactical level and can give various bonuses - and maluses - to its ability to fight, maneuver, and manage its logistics. The most important attribute for a commander is their martial skill; for each point of its commander's martial, an army will gain +5% assault ability, +1% enslavement efficiency, and +0.10 cohort loyalty gain chance as well as a bonus to dice rolls in combat, allowing well-lead armies to punch significantly above their weight in combat. An army without a commander will instead get a -15% land morale and +1% experience decay modifier, making them very vulnerable to a properly led army; even a weak, low martial commander is much better than not having a commander at all. A commander's traits, particularly any command traits, can also have effects on discipline, morale, reinforcement speed, and more.

Assigning commanders

The commander of a levy is usually the governor of the region the levy was raised from (even if the levy is split into multiple units, the governor will remain in command of all of them); as governors also have an important role in the administration of the region, this often requires balancing between a potential governor's finesse skill for administering the region and increasing its revenues and martial for leading levied armies during times of war, at least for heavily levy-dependent countries. In tribal countries, levies from all regions are instead split between the control of the clan chiefs. Being more specialized, each legion can instead have up to 4 dedicated commanders that can be assigned to legion, consisting of 1 Legate (who will be the legion's default commander) and up to 3 Tribunes. Each legion commander can only lead a single army of the legion at a time, but can be freely swapped out for another one of the legion's commanders (though this gives a temporary -5 loyalty malus). Like legions, migratory armies can simply have any character that does not already hold a position appointed to be their commander, and mercenaries come with their own commander when hired that cannot be replaced.

Loyalty

See also: Cohort loyalty

As the army's leader, a commander exerts a great degree of control over their commanded armies, which has significant implications for loyalty. The commander of a raised army will get +0.3 power base for every percentage of the country's currently raised armies (including raised levies, but not including unraised levies) they command, up to a maximum of +1.2 power base per cohort. Over time, and particularly when fighting in battles, each cohort will also have a chance to become loyal to its commander, scaling based on the general's charisma, martial, wealth, popularity, number of already loyal cohorts, and traits. A loyal cohort is tied even more closely to its sponsor than its commander, with their sponsor paying 33% of their maintenance (if relevant) and giving an even larger power base bonus ( +1 power base for each percentage of the country's army which is loyal to a character - even if that character is no longer the cohort's commander). If a loyal cohort is disbanded, they will become loyal veterans attached to their sponsor and continue to provide a smaller amount of power base. In addition to power base, both loyal cohorts and veterans also increase a character's popularity, family prestige, attraction as heir, and succession value - the last two particularly important for pretenders.

Note that a cohort can only give power base to a character once - if a cohort is loyal to a character who is also its current commander, that cohort will only count towards the proportion of loyal cohorts the character has, not commanded. This typically makes commanders one of the more powerful characters in a country, and loyalty can become a significant issue if they are already predisposed to become disloyal, whether through particular traits or from a pre-existing power base. Unless a character is very loyal, it is generally dangerous to allow a single character to take command over a large proportion of a country's army (except for the ruler, generally).

If an army has a disloyal commander, like other office holders they will refuse to give up their command (including any attempts to reorganize or disband the army) or follow any orders from the government. They will instead march around and (if relevant) engage in battles and sieges of their own accord, typically not actively sabotaging a country's war efforts but generally following their own interests and refusing to coordinate with other armies. This will usually significant decrease the overall effectiveness of the army in the war effort and can be especially problematic if at war with a dangerous enemy where focus and coordination is key. While a single disloyal commander is generally not a significant threat, if a civil war breaks out they will join the opposing side, along with all the cohorts under their command and turning their army against the country. Even if they are no longer a commander, characters siding with the rebellion will also bring along any loyal cohorts and veterans. A threatening commander can be removed from their post (including their governorship, if they are a governor) at any time using the Hold Triumph interaction if they have won a battle in the last 2 years at the cost of 30 political power, which can be useful for dealing with disloyal commanders (note that this only applies for appointed positions - the ruler cannot be given a triumph to remove them from the capital levy, and similarly clan chiefs cannot be removed from their tribal retinues this way).

Other effects

Commanders can gain wealth and popularity from winning battles and sacking cities and capitals; the latter is particularly useful with armies under the command of the ruler, as the loot is instead accrued directly to the treasury and popularity can easily be converted into political influence using the influence character interaction. Commanders also gain monthly family prestige based on the proportion of the country's army that are currently under their command, which altogether means that particularly successful commanders are often strong-performing candidates in republic elections, though the needs of being away from the capital to campaign means that they have a vastly reduced senate influence.

Reinforcement

Cohorts that have taken casualties through combat or attrition can restore their strength by drawing from a country's manpower pool through reinforcement. As long as there is manpower available, every cohort in an army can reinforce a certain baseline percentage of its total (maximum) strength each month depending on its circumstances:

• +10% (+50) per month in owned territories
• +5% (+25) per month if in enemy or uncolonized territory but adjacent to an owned territory, in occupied territory, or in neutral territory
• +3.75% (+18) per month if in enemy territory but adjacent to an occupied (but not owned) territory
• +2.5% (+12) per month for migratory armies in uncolonized territory
• +0.5% (+2) per month if otherwise in enemy territory, or for normal armies in an uncolonized territory that is not adjacent to an owned territory

The rate of reinforcement is then further modified by the country's, commander's, and army's reinforcement speed modifier. Reinforcing armies do not cost any extra gold, only manpower; if a country does not have enough manpower to meet all of that month's reinforcement needs, only some cohorts will be able to be reinforced that month.

Attrition

See also: Supply limit, Food#Army supply

Attrition is the loss of troops from non-combat related reasons, whether from disease, starvation, or simply desertion, and is a constant factor to keep in mind in warfare. Armies moving through hostile territory, or in general areas unable to properly support their needs, may suffer as many casualties as those directly involved in combat.

The amount of food and other resources an army needs is represented by its unit weight, which is the sum of the weights of each individual cohorts; each cohort has a base unit weight of 1, which is then adjusted by the Weight for Supply Limits value for its cohort type (less for light units such as light infantry and archers and more for heavier units such as heavy infantry and war elephants), which is then further modified by the army weight modifier. The army will then take 1 point of attrition for every point of unit weight it has above the supply limit of the territory it is currently in.

Some territories may also have a certain amount of base attrition, which is added onto any attrition from being over the supply limit (even if the army is not taking any attrition otherwise). Base attrition is given mostly by desert terrain and winter modifiers, as well as for besieging armies. The country hostile attrition modifier similarly gives attrition to all hostile armies inside a country's unoccupied territory. This means that it may occasionally be better to take a longer route that passes through more favourable terrain, particularly if the army has a high food demand and is not well-supplied. The automatic path-finding will prefer shorter movement times and low attrition when possible, but at times it might be better to cross that desert directly to reach the battlefield more quickly.

The attrition that a country's armies take is modified country-wide by the army attrition modifier and finally capped by the army's maximum attrition, with a base of 5% that can be increased up to 9% during harsh winters.

An army does not lose soldiers immediately upon taking attrition; instead, each point of attrition that the army is taking on the monthly tick will increase the army's food consumption by +10%. Only when an army runs out of food will it begin to take losses every month, with each cohort taking a certain amount of damage based on their Monthly Damage from Attrition modifier as a proportion of their total/potential (notably, not current) strength. For instance, a heavy infantry cohort has 5% Monthly Damage from Attrition, which means that if its army is out of food it will lose 25 soldiers each month, regardless of whether it is at full strength or has already been heavily depleted. This means that losses from running out of food are much more significant, relative to the army's current strength, for armies that are already partly depleted (whether from combat or previous losses to attrition), and for those that are disproportionately composed of heavier unit types.

Army movement

Armies move from one territory to another. Adjacent territories have a calculated distance between them, based largely on their size, and armies move a base distance per day (subject to modifiers). The movement cost modifier increases the amount of time needed for an army to move from the territory to another territory, effectively increasing the distance; many terrain types, particularly mountains, marshes, and jungles give significant modifiers to movement cost, while roads will signficiantly reduce it. The time to move from one territory to another then depends on the army's speed and the effective distance between the territories, but is always at least 1 day. As long as an army has not yet moved more than halfway towards the other territory, the movement order can be cancelled and the army will immediately stop moving (with all movement progress lost), but once an army has moved more than halfway from one territory to another, it will be considered to be movement locked and movement to the other territory can no longer be cancelled. If there is an enemy army that will be in the territory an army is moving to once it gets there, there will be an indicator showing the expected outcome of the battle.

Each cohort type has a specific movement speed, which is the baseline value of quickly it normally moves from one territory to another. A cohort's movement speed is then modified by the army movement speed modifier of its country, commander, and army, as well as on a cohort type-specific basis by the individual unit type movement speed modifiers, all given mainly by inventions and military traditions. The army movement without roads modifier (used for armies that are building roads) is also applied, but only if there is no road connecting the two territories the cohort's army is moving between. The movement speed of an army is then the movement speed of its slowest cohort.

Army actions

Besides moving to different locations, armies can also be ordered to do a large number of actions, some military, some political, and some economic, and there are various toggles and settings that can be changed to tailor the behaviour of the army. Note that many actions have restrictions, and no actions can be done on armies with disloyal commanders.

Organization

• Create New Unit - Allows splitting off of cohorts from an army to create a unit.
• Consolidate - Merges manpower depleted cohorts of the same type, and then removes empty cohorts. Cohorts loyal to a character cannot be consolidated away.
• Detach Siege - Splits the army and leaves behind an army just large enough to siege or occupy the current city.
• Detach Support - Splits off all supply trains into a new army, leaving most of the food with the main army. Useful for resupplying.
• Split in Half - Splits the army as evenly in half as possible.
• Disband - Removes the unit with all its cohorts (or terminates employment for mercenaries) and, for legions, restores 25% of used manpower back to the pool. Costs 25% of the total recruitment cost of each cohort disbanded for legions. Cannot be used on levies, who must be disbanded from the military screen.
• Merge Units - Merge together 2 or more armies into a single army. Can only be used on armies of the same type and, for levies and legions, of the same region.
• Reorganize Units - Transfer cohorts between 2 armies of the same type and, for levies and legions, of the same region.

None of these actions, except for disbanding, can be used on mercenaries.

Menus

• Select Objective – Can select an objective for this unit, which will allow it to act mostly independently while trying to follow a broad objective given by the player.
• Select Tactics – Change the combat tactic of the unit, which affects combat effectiveness based on the unit composition and the combat tactic used by enemy armies.
• Select Preferred Flank Size - Select the preferred size of the flanks, where the flanking cohorts will be placed.
• Select Primary Cohort - Select the unit type that will be preferentially placed in the front row during battle, where they will be the first to engage the enemy.
• Select Secondary Cohort - Select the unit type that will be preferentially placed in the second row during battle, where they will engage only after the primary cohorts (first row) have fled or been destroyed.
• Select Flanking Cohort - Select the unit type that will be preferentially placed in the flanks during battle, where they will try to encircle and cut down enemy cohorts.

Toggles

• Allow Attachment – Allows other units to attach to the current army, which will make them automatically follow the army as closely as possible.
• Build Road – Instructs the army to build roads between owned, subject, or uncolonized territories while moving, improving movement speed and giving small economic bonuses. Building roads costs a base of 50 gold (reduced to 10 gold if the army has at least 1 engineer cohort) and gives significant penalties to morale, movement speed (when not on roads), and maintenance cost. Requires Civic Advances to be greater than 4, and that the army has at least 10 cohorts.
• Drill Army – Gives +2.50% monthly experience gain in exchange for +33% legion maintenance cost and +1 cohort loyalty gain chance, allowing an army to improve or maintain its level during peacetime for improved efficacy in combat and military experience gain. Requires a commander and at least normal default army maintenance in economic policies, and the army cannot move, fight or siege while drilling. Can only be done with legions.
• Force March – Gives +50% army movement speed in return for +50% army weight modifier and −100% army morale recovery. Useful for quickly moving an army to where it is needed, particularly if it is already at full morale, but will almost completely stop an army from recovering morale if low. Requires the Quick March Martial Invention.
• Build Military Road – An improved version of the standard Build Road unit ability that costs only 25 gold without an engineer cohort (remains 10 gold the army does have one) and with no maluses to army morale or maintenance cost. Requires the Roman Roads tradition in the Roman Traditions tree (no advances level requirement) and that the army has at least 5 cohorts, and is available only to legions.
• Unit Reorganization – Gives +25% reinforcement speed and +10% army morale recovery in exchange for +100% maintenance and −33% movement speed, allowing an army to quickly recover from losses. Particularly useful for shortening the time for mercenaries to become battle ready, if it can be afforded. Can only be done in friendly (owned, allied or subject) owned and controlled territory.

Attachment

• Attach to Unit – Attach to another unit present in the same territory that has attachment allowed. An attached army will follow the army it is attached to as closely as possible to without further input, allowing for the grouping of armies from different types or regions that cannot be merged together.
• Detach from Unit - Detach the army from the unit it is currently attached to and following.
• Embark Army - Embark the army onto an owned fleet in the territory that is large enough to carry the army and not currently moving in preparation for naval transport. A navy must have at least as many ships as the army does cohorts to carry it, and the territory must have a port for the navy to dock.
• Disembark Army - Disembark the army from the fleet it is currently in onto the territory. Requires that the navy is currently docked in a friendly territory with a port.

Unit abilities

Most unit abilities are quite specialized and have either government or military tradition requirements.

• Anabasis – The ruler, as the commander of an army, goes on the tour of the local province, increasing province loyalty instantly by 5 and then by +0.25 for 2 years at the cost of 15 political influence. Only available to monarchies if the ruler is commanding an army in the province capital, and can be done every 2 years per province.
• Construct Border Fort – Builds a level 1 fort in border territory or neighbouring uncolonized territory for 1500 manpower. Can be used to colonize neighbouring territories, which also creates a freemen pop of primary culture and religion. Requires the Castra military tradition in the Italic Tribe Traditions tree, an army with at least 5 cohorts, and that the territory has no neighbouring owned forts.
• Desecrate Holy Site – Destroys a holy site in a controlled (not necessarily owned) territory for 2 aggressive expansion, angering followers of its religion and weakening its owner. Any sacred treasures in the holy site will be seize and transferred to the army's owner's reliquary. Gives 10 stability if the country has the Militant Epicureanism Religious invention.
• Military Colonies – Creates a freeman pop of primary culture and religion in a territory with no more than 5 pops located inside a loyal province, at the cost of 1500 manpower, 15 province loyalty, and loyalty for a random cohort in the army (or 1 tyranny if the commander is the ruler of a non-republic). Requires either the Military Colonies (Greek Kingdom Traditions), Kleruchoi (Persian Traditions), or Colonial Integration (Levantine Kingdom Traditions) military traditions and an army with at least 5 cohorts.
• Order Full Retreat – Gives the order for the unit to perform a shattered retreat from foreign territory or a battle, at the cost of 50% of the army's current strength. This can be useful for armies trapped deep in enemy territory or cut off by hostile forts.
• Pillage – Sack a city, metropolis, or province capital with at least 20 civilization value owned by another country. If the territory has a fort, it must also be occupied. Gives political influence equal to 1/80 of the territory's civilization value multiplied by its population (with a minimum of 1) and 2.4 gold per pop (up to 2.4 times the cohorts in the army). The pillaged territory gets −25% local population growth and −25% local tax for 5 years, and the owner will lose −50 opinion of the pillaging country with a yearly decay of 2, stacking up to –200. If the territory's owner already has less than −100 opinion of the pillaging country before the action was taken, the army's owner will declare war on the territory's owner with the Superiority wargoal if they are not already at war. Only available to Migratory Tribes, and only on territories that were not pillaged or razed in the last 5 years.
• Raze City – Raze a city, metropolis, or province capital with at least 5 civilization value owned by another country. If the territory has a fort, it must also be occupied. Halves the civilization value in the territory and gives an additional -0.01 monthly civilization change, converting it to research progress equal to 1/8 the civilization value destroyed for each research category where the territory's owner is more advanced than the army's owner. Costs 2 aggressive expansion and −50 opinion with the owner with a yearly decay of 2, stacking up to −200. If the territory's owner already has less than −100 opinion of the pillaging country before the action was taken, the army's owner will declare war on the territory's owner with the Superiority wargoal if they are not already at war. Only available to Tribes, and only on territories that were not pillaged or razed in the last 5 years.
• Root Out Pirates – Removes the Pirate Haven modifier from an controlled (not necessarily owned) province that has it. Requires the Anti-Piracy Edict (for monarchies), Anti-Piracy Statutes (for republics), or Lex Claudia (for Roman republics) laws, and is not available to tribes.
• Settle – Settles migratory armies in an owned, controlled, or uncolonized territory, converting each migratory cohort into a tribesman of the primary culture and religion. Will colonize the territory if uncolonized or seized from another country if occupied, and requires that there be more migratory cohorts in the army than pops in the territory if the territory is currently unowned. If colonizing or seizing a territory, only the minimum number of cohorts required to match the current population will be settled. Only available for migratory tribes.

Unit objectives

Unit objectives allow a player to automate individual armies and issue broad orders that they will try to follow under the control of the AI, outsourcing the management of some (or all) armies using the same processes that the AI of other countries uses to control its armies and navies. An objective can be selected for each army or navy under player control (or several units at once, in which case the objective is applied to each of the selected armies/navies), which enables AI control over the selected units and allows it automatically move around, sieging territories, engaging enemies, or avoiding hostile forces depending on the selected object. Armies with a selected objective can also be assigned any number of regions, which it will try to restrict its operations to. While usually not as effective or efficient as manual country of armies, automated armies are generally sufficient to deal with regions or fronts where they already have local superiority.

Available objectives

• No Objective: The unit remains idle unless ordered by the player. This is the default for all player-controlled armies, and can be selected in order to disable army automation.
• Independent Operations: The unit acts independently, engaging enemy armies and occupying enemy territories as it sees fit. Generally mimics default AI behaviour.
• Defend Borders: The army will stay inside friendly borders, fighting enemy armies that enter and retaking occupied territories.
• Carpet Siege: Focuses on occupying and taking control of enemy territories, while generally ignoring already controlled territory.
• Reconnaissance: Patrols across the country's borders reporting on enemy movements.
• Keep in Reserve: The army will stay within the country's borders and actively avoid contact with the enemy unless superior.

Special objectives

There are also many unit objectives that cannot be picked but that may still be encountered, especially in AI behaviour.

• Disloyal: Used by disloyal commanders and mercenaries when in deficit. Besides ignoring all orders from above, disloyal armies will prefer to remain at home and avoid enemy territory and armies in order to preserve their strength for any future rebellions.
• Slave Revolt: Slave revolts will target more populated territories to loot and set free more slaves as well as avoiding fortified territories that delays their progress and allows the country's military to organize.
• Migration: AI migratory armies will look choose a particular migration target to concentrate their migratory armies, and otherwise try to stay near already owned territory, avoid other countries, and avoid engaging with any enemy armies.

Warfare

Naval warfare

Navy

Mechanics