While visiting northern Brittany in AD 122, Roman Emperor Hadrian Augustus witnessed the consequences of the war between his armies and the savage Picts. In a display of Roman power, he ordered the construction of a wall that would separate the Picts tribes from the rest of England. Large in design, the wall stretched from sea to sea. Hadrian's Wall remained in the service of the Roman Empire for almost 300 years. Today, Hadrian's Wall is a UNESCO World Heritage Site and the remains of forts, towers and turrets can still be visited.

Players take on the role of a Roman general tasked with building a castellum miliarium and an adjoining wall. For six years (game turns), players will build their fort and wall, secure defenses and attract civilians by building services and providing entertainment - while defending the honor of the Roman Empire against the Picts in war. The player who can accumulate the most fame, piety, bravery and discipline, while avoiding disdain, will prove to the Emperor that he is the model Roman citizen and will be crowned Legatus Legionis!