He reached the brow of the ridge, and overlooked the Danes’ encampment.

The camp was set out like a letter ‘D‘, with a half-circle of palisades and ditches pressed against a stretch of river bank. Arngrim could see tents of leather and sail-cloth, threads of smoke rising up from fires, horses corralled loosely. The ships had been hauled up on to the mud, their shallow draughts having enabled them to navigate even this far inland. The Danes always built their camps this way. They rode to battle on plundered horses and fought on foot, but they always preferred not to be too far away from their ships. Indeed it was said that you could wound a Dane more deeply by burning his ship than by striking down his son.

The warriors went about their business amid heaps of English treasure, extracted from the burned ruins of Alfred’s hall. There were gangs of captives too, thegns, perhaps even ealdormen, great men of the kingdom of Wessex sitting in their own shit and tied together with lengths of rope like cattle. The Danes ignored the English save to prod them with their swords or piss on them, or they would pluck out a girl or a woman to be dragged into one of the tents.

Arngrim was close enough to hear scraps of the Danes’ conversation. There was talk of taking the booty and captives back to Eoforwic - which the Danes called Jorvik, a captured town which was becoming a major market for the Danes. Meanwhile they were planning to use Cippanhamm as their base in Wessex for the rest of the winter. This riverside camp would serve as their river port, and a shelter for the ships. The assault on Cippanhamm was a classic example of the Vikings’ way of working, Arngrim reflected, as every English thegn had learned from hard experience: surprise, attacks at night, the use of forests for cover, the ability to throw up rapid fortifications, their willingness to move into English settlements and use them as bases.

Arngrim did not see the Danes’ leader, the petty king Guthrum. Nor did he spy Egil, the brutish leader of the war band.

‘Hsst! Hsst!’

The call was loud enough to make Arngrim flinch. He looked back to the ragged copse at the bottom of this low ridge, where he had left Ibn Zuhr and Cynewulf. There was no sign of the Moor, but Cynewulf was standing in the open air, his habit streaked with dirt, filthy hair standing up around his tonsured scalp.

Furious, Arngrim waved him back. With one last glimpse down at the Danes he slithered on his belly down the ridge.

He met the others in the gloom of the forest. ‘By Woden’s eyes, what are you doing? Do you long for death, priest?’