William I established a castle at Lincoln, one of numerous Royal constructions, as part of his campaign to suppress a wide-scale revolt in the north in the years immediately following the Norman invasion. By the time of the Norman invasion the town had a substantial community. As the Vikings started to dominate northern England in the ninth century AD, Lincoln once again became a major settlement with its position on the River Witham supporting a thriving overseas trade. Roman administration in Britain came to an end in the early fifth century and Lincoln went into decline although archaeological evidence suggests it remained occupied. Over the long occupation of this colony the defences of the town were enhanced and rebuilt in stone вЂ“ predominantly to serve as a status symbol rather than to meet any defensive requirement. When, in the early fourth century, the province was sub-divided into four administrative areas, Lincoln became the district capital of Britannia Secunda. The town continued to grow and, aided by the construction of the Fossdyke (a canal connecting the Rivers Witham and Trent) in AD 120, became one of the most important Roman settlements in Britain. Known as Lindum Colonia, the site was vastly expanded from the former confines of the Roman fort and eventually extended down to the waterfront. However, despite this withdrawal the fortress at Lincoln was left intact and, by the late first century AD, had been converted into a colony for retiring veterans from the army. This force, which had only been founded the previous year, occupied the site until AD 79 when they were withdrawn to form part of General AgricolaвЂ™s assault on modern day Scotland. It is likely that the Ninth Legion used this base to mount operations against the troublesome tribes in the Peak District.ДЄround AD 70 the Ninth Legion moved north to York and were replaced by the Second Adiutrix Legion ( Legio II Adiutrix Pia Fidelis). Ermine Street, the Roman road from London, ran north/south through the fort whilst Fosse Way, the road to Exeter and the first Roman 'frontier' in Britain, ran south-west. It was configured in a traditional Roman layout with a Headquarters building and Commanding OfficerвЂ™s house in the centre of the site surrounded by workshops, barracks and granaries.

The fortress was an earth and timber construction capable of garrisoning around 5,000 troops and enclosed 41 acres. At the time this was their northernmost Legion with the land beyond controlled by the pro-Roman Brigantes tribe who formed a buffer between the empire and the Caledonian tribes in modern day Scotland. They established a Legionary fortress on the site as a base for the Ninth Legion ( Legio IX Hispana) around AD 60.

Coupled with its proximity to the Brayford Pool, originally a broad water where the Rivers Till and Witham converged, it was immediately recognised by the Romans as a strategic location. Sited on top of a steep escarpment overlooking an otherwise low-lying landscape, Lincoln dominates the surrounding countryside.

Viking conquest roman fort