Europa Barbarorum (), or EB, is a modification of the PC game Rome: Total War (RTW) based on the desire to provide Rome: Total War players with a more historically accurate game experience.

The basic gameplay mechanics of the original game remain the same. The player controls an empire with the goal of conquering as much territory as possible and eliminating rival factions, which are controlled by the computer, or AI. The main campaign is split between two gameplay modes: a turn-based strategy map for moving whole armies and managing the empire, and a real-time battle map for fighting battles on the ground between two or more armies. The two game modes are linked, with success or failure in one game mode influencing the chances of success or failure in the other.

Although set in a similar historical period and geographical area to the unmodified game (covering a timespan of 272 BC to 14 AD, compared to the original game's 270 BC to 14 AD), Europa Barbarorum is a total conversion modification as it replaces all the aspects of the original Rome: Total War game that can be replaced, such as unit models, statistics and the musical score. The modification has received favourable reviews in a number of computer gaming magazines. PC Gamer magazine ranks Europa Barbarorum as the best mod for any of the seven Total War games released for the PC at that time.

Gameplay In the original Rome: Total War, the player took control of an empire, or "faction", of classical Europe, North Africa or the Middle East, with the aim of expanding their faction's territory and eliminating rival empires through military conquest and city-building. Europa Barbarorum retains this basic gameplay mechanic and sets itself in a similar time period and geographical area to the original game. However, as a total conversion the mod replaces the particular factions, military units, buildings, and other elements present in the original game, and adds a new soundtrack and several brand-new gameplay mechanics not present in the original, such as the installation of puppet rulers. The modification's development team's stated aim in making the changes that they have to Rome: Total War is to make the player's experience of the ancient world more historically accurate. For this reason, numerous parameters of the game at the start of the campaign in 272 BC, such as generals' names, the diplomatic relations between factions, and the particular understanding of the outside world that each faction has, have been set to correspond to the actual political situation in that year.

Also for reasons of historical verisimilitude, factions, provinces on the campaign map and factions' family members have been given vernacular names in Europa Barbarorum, rather than having Latinized or Anglicized ones, as in Rome: Total War. So, for instance, the original game's Armenia faction is known as Hayasdan in Europa Barbarorum, and Germania as the Sweboz. Instead of having to play one's first campaign as a Roman faction and only subsequently unlock playable campaigns as non-Romans by defeating them in the Roman campaign, all twenty of Europa Barbarorums playable factions can be accessed by the player from the start. Furthermore, the one unplayable and three playable Roman factions of the original have been combined into a single playable faction in Europa Barbarorum, the Romani. Dissatisfied with the homogeneity of the factions of the original Rome: Total War, the Europa Barbarorum development team has sought to differentiate the playing experiences of the game's different factions. So, for example, Rome: Total Wars trait-acquisition system, where the player's faction's family members acquire certain characteristics and talents which make them more or less adept at certain tasks such as city management or military leadership, has been made more faction-specific in Europa Barbarorum, with Hellenic characters' traits, for instance, being based on Theophrastos' Characters and Aristotle's teachings on the Golden Mean, and Romans' traits being partially based on the moral tales of Valerius Maximus. There are sometimes additional requirements for a family member to be able to gain a new trait: in order for them to compete in one of the Panhellenic Games, for instance, the player must ensure that they are stationed in the appropriate city on the campaign map in the year that the competition is scheduled to take place. One reviewer has commented that Europa Barbarorums expansions upon the original Rome: Total Wars trait system have served to add a role-playing element to the game.

Campaign

As in the original Rome: Total War, Europa Barbarorums strategic campaign sees the player take control of a particular faction and then compete for territory and resources against all the other factions, which are controlled by the game's artificial intelligence. The player is presented with a map of Europe, North Africa and the Near East in which territory is divided into 200 provinces, each of which contains a province capital, which will at any given point be controlled either by the player's faction, a rival playable faction, or the non-playable Eleutheroi faction, which represents the world's minor kingdoms, regional powers and rebel states. If a faction should at any point find itself not in control of any provinces, it is eliminated from the game. Gameplay is turn-based, each turn representing the passage of three months on the campaign map (unlike the six months of the original Rome: Total War) and alternating between the player managing their empire and the artificial intelligence making all the other factions' moves. A key game mechanic of the campaign map is the annexation of territory, which is done province-by-province, either by successfully besieging the province capital, or by acquiring it from another faction through diplomacy. Once a faction has acquired a province, they may construct buildings in the province capital that either enable the recruitment of certain military units or grant various bonuses to the city, such as greater resilience during a siege or a decreased likelihood of the province rebelling. Provided the city contains the appropriate buildings, the player may recruit military units in the city at the same time as undertaking construction projects. The aim of the game is to acquire a specified number of provinces and/or eliminate specified rival factions (in Europa Barbarorum particular victory conditions differ for each faction), whilst avoiding being eliminated by the other factions.

The campaign map itself of Europa Barbarorum covers a wider geographical area than that of Rome: Total War, expanding into areas such as the Arabian Peninsula, India, Central Asia, and Scandinavia. Relief, province boundaries, snow boundaries, vegetation types, coastlines and areas prone to natural disaster in 272 BC have all been researched and implemented into the campaign map. The Nile–Red Sea canal linking the Indian Ocean and Mediterranean Sea has been added to the map, as have the great trade routes of the ancient world, such as the Amber and Silk Roads, which can be captured and exploited by the player or by the artificial intelligence.

The selection of factions present in the original Rome: Total War has been overhauled in Europa Barbarorum. The original game's Gaul faction has been replaced with two new factions, the Aedui and the Arverni. The Scythia faction has been replaced by the Sauromatae, and the Greek Cities faction (which included various city-states) has been replaced by the Koinon Hellenon (), a faction which represents the Chremonidean League of Athens, Sparta and Rhodes. Entirely new factions include Baktria, a Central Asian Hellenic empire, and Epeiros, a western Greek faction famous for producing Pyrrhos of Epiros. On the other hand, the Numidia faction of Rome: Total War was removed entirely.

The way in which factions enhance the provinces they own through the construction of new buildings in their province capitals has changed in Europa Barbarorum. The process of assimilating a newly conquered province into one's empire has become more differentiated in the modification than it was in the original game through the introduction of so-called "government buildings" and military–industrial complexes. Government buildings represent different degrees of central State intervention in a province, and range from a homeland government, which can only be built in a faction's traditional ethnic homeland and represents the highest possible degree of central State control, to an allied state government, which makes the province in question semi-autonomous and installs a puppet ruler to govern it on the controlling faction's behalf. The choice of government building in a province affects what other buildings can be constructed there: the greater the degree of autonomy granted to a province, the greater the shift in the make-up of the pool of buildings available for construction from the controlling faction's own buildings to native buildings; that is, buildings which are more closely associated with the faction that would make its traditional home in the province in question, rather than the one currently occupying it. Nomadic, desert- and steppe-dwelling factions have their own government buildings, which some say has helped differentiate between Europa Barbarorums factions and make the differences between Europa Barbarorum and the original Rome: Total War more than just cosmetic. These government buildings also affect unit recruitment options in a province, through the mod's introduction of military–industrial complex ("MIC") buildings. The original Rome: Total Wars system of constructing and subsequently upgrading different types of building in order to recruit different types of soldier (stables for horses, ranges for archers, and so on) has been replaced in Europa Barbarorum by the "factional MIC", which enables the recruitment of all the province-controlling faction's units, and the "regional MIC", which enables the recruitment of native types of soldier. How far the two types of complexes can be upgraded depends on the government of the province: the greater the autonomy of the province, the more the native MIC may be upgraded, and the less the factional MIC may be upgraded; and vice versa. In addition to buildings that can be constructed by the player, Europa Barbarorum also introduces a number of unique buildings or "wonders", which can either be man-made structures or features of the landscape, and which provide unique bonuses to the province.

Warfare

If, during their turn on the campaign map, the player should engage one of their armies in combat with another faction's army, or if their troops should be engaged by another faction during the AI's turn, the player then has the option of fighting a real-time battle or siege. In this gameplay mode, the player directs the troops they had brought with them on the campaign map to the engagement, ordering them to manoeuvre and attack the enemy's troops on a three-dimensional battlefield. Troops can either be killed outright on the battlefield or made to rout and flee the field if their morale falls below a certain threshold. Reviewers have noted of Rome: Total War that, during a battle, troop numbers do not outweigh all other considerations; other factors such as individual unit types' strengths and soldiers' morale and fatigue at the point of fighting are also taken into account. A battle is won when one side kills or routs the entire enemy army; a siege may be won by the attacking side through either dispatching the opposing forces or gaining control of the besieged city's central plaza for a certain number of minutes, and by the defending side either by killing the attackers or by destroying their siege equipment before they have managed to breach the city's defences.