948 - Vikings reconquered York

Eric Bloodaxe
Eadred pillaged in Northumbria  he burnt Saint Wilfrid's church at Ripon, but he was attacked near Castleford where he lost many troops.
An ambush on the Orkney Islands killed Paal and Erlend.
Eric Bloodaxe conquered York, he was the last viking king to rule in York.
Pope Agapitus gave the Archbishop in Hamburg, Adaldag the right to introduce bishops in Scandinavia and 3 German monks were appointed as bishops in Ribe(the Frisian Liufdag), Hedeby(Hored) and Reginbrand in Aarhus, where a church had been build, they were also responsible for the Christian mission in the rest of Scandinavia, because in these areas it was not possible to establish bishops.
Runestone from Aarhus

Aarhus an important trading center, was furnished with a wall for protection against pirates. Written sources tell us that the town was threatened by invasion several times, and archaeological investigations have shown that the fortifications were extended and strengthened both in the 11th century and later. The wall was in the form of a horseshoe, with its open side towards the sea. Remains of a marine barrier show that the town had a protected harbor. The defensive earthwork was about 20 m thick and 4 m high, enclosing an area of about 240 acres.
Bishop Reginbrand at Moesgaard Museum