generation13

In 893 Vikings raided Chester, then 'a deserted city in Wirral'. The raid, which culminated in the Danes' occupying the city and being besieged there for two days while the English ravaged the surrounding districts, may well have been prompted by an awareness of the city's growing economic and strategic importance, lying as it did near a direct route between the already closely linked Scandinavian kingdoms of Dublin and York and the Old Rhine to Leyden. The area south of the legionary fortress was occupied by the late 9th century; in particular, a site at Lower Bridge Street has yielded the remains of a small sunken-featured hut, a late 9th-century brooch, and sherds of a Carolingian jar imported from northern France.

Moreover, from c. 890 Chester is the most likely site of a mint known to have operated in northwest Mercia. By then, therefore, the city was presumably a place of some importance.

The history of medieval Chester can be said to begin only in 907 with the refortification of the site by the ruler of Mercia, King Alfred's daughter Æthelflæd. The background to that event was the establishment of a Hiberno-Norse community in Wirral after its expulsion from Dublin in 902. It seems that the exiles, led by Hingamund, were granted land in Wirral by Æthelflæd and her husband Æthelred but soon afterwards cast covetous eyes on the wealth of Chester, only to be repulsed by the great army which she assembled in the city. The story, although preserved only in a late source, has been shown to be reliable in essentials, and confirms that any desertion of the city was temporary.

The location of the walls erected c. 907 is unknown. That, as might be expected, Æthelflæd adapted or at least reused in part the Roman defences is suggested by the laying of a gravel road parallel to the inner side of the walls in the early 10th century. Such an action implies that the Roman west wall, which later disappeared, was then largely intact; in the 12th century Holy Trinity church was apparently built upon the remains of its gate, and its line was still traceable in the 14th century, when refuse was dumped into the foundations. The Roman walls were perhaps refurbished in their entirety as a defensible inner core, the total enceinte being enlarged by extending the north and east walls to the river to form an L-shaped fortification with the Dee as the main defence to the south and west. The length of walls kept in a defensible state seems to have been consonant with a formula recorded for Wessex in the Burghal Hidage, which stated that every hide of land assigned to the maintenance of a burh sufficed to provide one man, and that every pole (c. 5 metres) of fortress wall required four men to defend it. The formula probably applied to Chester, whose reeve in the mid 11th century used to call up one man from each hide of the county to repair the walls and bridge.

Defences in that form are also consistent with signs of late Anglo-Saxon, perhaps 10th-century, occupation in Lower Bridge Street, north of the river but outside the Roman defences. Though it is no longer possible to accept without qualification the suggestion that Wolfeld's Gate, which was in that stretch of wall, bore a Scandinavian personal name most likely to have been used before 1066, the fact that the wall divided the burh proper from 'Redcliff' remains significant; 'Redcliff' was the focus of the ecclesiastical enclave known as the bishop's borough, which was probably from early times surrounded by its own ditch.