- Athaulf (Goths) is camping in the west of Rome, and the player will assume command over his camp, consisting of a Town Center, a mill, a few farms, two barracks, and a few pavilions. However, the player will not take over his troops apart from himself.
- Goths (Goths) are under Alaric's command, invading Rome from the east. The player will first take over their ram and some knights and Huskarls to attack the east gate, and the take over a few other soldiers to help fend off the Legion reinforcements from the east. At the end of the game, Alaric will bring in a larger troops to sack Rome from the breached east gate.
- Rome (Italians) consist of civilians who are neutral in the conflict and care only their own livelihood and survival. Once the player selects Athaulf to indicate readiness to invade Rome from the west, the Romans will invite the Goth invaders to enter, and the gate immediately facing Athaulf's (which is the player's) camp will be unlocked and given to the player.
- City guard (Italians) is guarding Rome, and they are made up of Legionaries, pikemen, Condottieri, Genoese Crossbowmen, crossbowmen, knights, etc. They have a large band of marching guards at the south gate of Rome.
- Imperial Legion (Italians) is reinforcing the Roman city guards from outside the city. They have two camps - one in the west, another in the middle of the map, just immediate south of Rome. Their forces are primarily made up of Legionaries, knights, crossbowmen, etc. Their reinforcement from the east (after the east gate is being destroyed) also includes Huskarls. They would start producing more units at the camps once the player begins attacking Rome (upon selecting Athaulf), which would also include cavalry archers and the siege weapons. After the player takes over Athaulf's camp, the Legions would keep sending small group of reinforcement from the southwest, heading towards the camp.
The player will first witness the Goth army under Alaric attacking three towers on the eastern side of Rome, then the player will be given a battering ram, eight Huskarls and some knights to destroy the east gate of Rome. At this moment, there would be some Legion reinforcements attacking from the east, trying to stop the player's siege while being intercepted by the Goth army.
Once the gate is down (in the official HD edition Forgotten expansion, the ram would be deleted/destroyed automatically), another batch of Legion reinforcement would attack from the eastern corner of the map, and the player would take over some of the Gothic troops to repel the Legions.
Alaric will order the courier (a Light Cavalry with boosted hitpoints) to send the attack order to Athaulf, who is on the western side of Rome. The courier must survive until he meets Athaulf (in the original unofficial mod Forgotten Empires, there are three outlaws (labeled "OUTLW") near the courier's starting point, but they can be killed quite easily with only one strike). There are marching city guards along the road to the south gate of Rome, so the courier must avoid them. There are two possible paths for the courier to take: the longer but much safer path would be travelling through the forest in the south, and only having to deal with four Legion archers and being shot by two city guard towers; the shorter path is much more dangerous, having to pass by a Legion camp and must race through the troops.
As Athaulf receives Alaric's order, he would order to get the trebuchets ready, but suddenly attacked by Legions. After a bloody battle, Athaulf would go to his base and order the villagers to gather foods for the troops. The player would be given some of the villagers and the mill for the job, aiming to collect 250 food. The player may do so by hunting, collecting from berry bushes, or usurping Athaulf's farms.
As the objective is achieved, the player would take over Athaulf himself and the entire base, but not his army. Whenever the player is ready to attack Rome, simply click on Athaulf. Clicking on Athaulf would trigger the Roman civilians to unlock the gate where Athaulf's troops are facing, and the gate will be given to the player. The Roman guards at the Arch of Constantine would start defending the Arch (their ownership transferred from "Rome" to "City guards") except a pikeman who would escort Galla Placidia to the Mausoleum of Hadrian. Athaulf is to go to the Arch of Constantine.
After that, Athaulf is to proceed to the Mausoleum of Hadrian to meet Galla Placidia, and Alaric will send another troops to sack Rome from the east, and the scenario is won.
While the player is preparing the troops for Athaulf's side, the Legions would keep sending reinforcements from the road on the west of the base, aiming to attack the player's base. The player may simply build walls, gates and towers to defend against them, and it would greatly help if the towers are garrisoned with archers or crossbowmen. If the player selects Athaulf to begin the attack on Rome, the Legions will start building troops at both of their camps, therefore it is advisable that the player destroys both of the camps.
Even before the player officially starts invading Rome by selecting Athaulf, it is already possible for the player to enter Rome by the westernmost gate. The city guards in Rome consist of pikemen, Condottieri, Genoese crossbowmen, crossbowmen, knights, and Legionaries. Both of the crossbowmen can be easily taken down with skirmishers and Huskarls, while the knights can be easily taken down by large group of pikemen or halberdiers. The guards at the Arch of Constantinople consist of an overwhelming majority of pikemen, with a few Legionaries and one Centurion. The player's force should primarily consist of infantry, as the pikemen and Genoese crossbowmen are a great threat towards cavalry.
The player can find a few gold mines around the base taken over from Athaulf, and once the gold mines are exhausted and the surroundings is safe, the player may trade with any market. If the player wishes to trade with the civilian markets in Rome, the player should eliminate the nearby city guards to keep the Trade Cart safe. If the player wishes to trade with the Legions' market in their east camp, the player should eliminate all the troops and raze all the military buildings to prevent them from creating new units which would harm the Trade Cart. The player may also build a dock to trade with any of the civilian docks.
While there is just a handful of stone mines at the base, the player can find a few more on the western side of the river, a few in the southeast of Rome where the courier started his journey to meet Athaulf, and a few more on the east of Rome where Alaric is situated at. To mine on the western side of the river, all the four Legion archers must be killed, and both of the city guard towers must be destroyed.
- This is the only scenario of the campaign where the player may advance to the Imperial Age and also the only scenario where the player does not control Alaric himself.
- There is an easter egg in this scenario - in the east of Rome, there is a throwing axeman named "CAELIR" standing in the middle of a cleared forest, and if he is selected, he would call to chop down the trees. This area is visible if the player researched Spies or use cheat.
- In the original unofficial mod Forgotten Empires, in the part order the courier send attack order to Athauf, there are three outlaws (labeled "OUTLW" in the form of Archer) near the courier's starting point, but they can be killed quite easily with only one strike. Those units were meant to spawn randomly near trade routes, and rob the Villagers and Trade Carts but was scrapped.
- Athaulf married Galla Placidia in 414, which was after Alaric's death and he took over as the king of the Visigoths.