Before the Roman invasion of Britain, the present-day area of Manchester was dominated by a warlike Celtic tribe. In the battles against the Celts, the Roman general Gnaeus Julius Agricola became famous. Around AD 79 Agricola built a wooden military fortress at the spot where the rivers Medlock and Irwell met, called Mamucium (breast-shaped hill in Celtic), which was rebuilt in stone several times. As it occupied a strategic position, it became a permanent feature of the area. The fortress was located at the point where the Irwell River could be crossed by a road leading north through a Roman fort (today the village of Ribchester) to a defended zone that included Hadrian’s Wall, a stone wall built by the Romans across Britain with the aim to prevent raids of Scottish tribes to the north.

A transport artery also connected the strategic legionary bases of York and Chester at the site of Mamucium, which was guarded by Roman mercenary troops, with some of them coming from an area in present-day Austria.

In turn, a civilian settlement soon developed and served the needs of the garrison. Important discoveries associated with this settlement include several altars, a Christian word square and remnants of a Mithraic temple. The word square is an extremely rare find and is thought to have been used by early Christians as a way to identify each other.

The fortress was abandoned during the Dark Ages. English King Edward the Elder sent troops to occupy the fort as a part of the Mercian kingdom. It isn’t clear, however, what location was meant, because the centre of the settlement moved to the confluence of the Irk and Irwell rivers in Saxon times. Later, the fortress fell into disuse and even came to serve as a source of construction materials.

The remnants of the fortress were visible until the 1700s, when a railway was built across the fort area, much of which was destroyed. A reconstruction of a gate, the foundations of some civilian buildings and a section of a wall (all parts of a Roman fortress) can be seen at the historic site of Castlefield in Manchester. The settlement was known as Mameceaster in Anglo-Saxon because it incorporates the former Celtic name.