‘When [the Danes] were in the east, the English army was kept in the west, and when they were in the south, our army was in the north. Then all the councillors were summoned to the king, and it was then to be decided how this country was to be defended. But even if anything was then decided, it did not last even a month. Finally there was no leader who would collect an army, but each fled as best he could, and in the end no shire would even help the next’.
In September 1011, Thorkell laid siege to Canterbury. The city fell three weeks later: a traitor opened the gates. Thorkell took a good haul of valuable captives, including Ælfheah, the archbishop of Canterbury. Æthelred finally called for a truce over the winter and at Easter Thorkell was paid gafol of 48,000 pounds (21,772 kg). England’s defences might have been collapsing but its bureaucracy was still functioning efficiently and Æthelred’s tax collectors had no difficulty raising even this enormous amount of money from his long-suffering subjects. The payment did not save Ælfheah. The Danes wanted another 3,000 pounds (1,361 kg) ransom for his release, but the archbishop refused to allow anyone to pay it, apparently so as to spare the peasantry further burdens. On the Saturday after Easter (19 April 1012), Ælfheah’s captors got good and drunk and gave vent to their frustration with their unco-operative prisoner. They battered the archbishop with bones and ox heads and then one of the Danes killed him with an axe blow to the head. Thorkell seems to have tried to save the hostage, promising his men silver and gold if they would spare him, but to no avail. Even in such violent times, the murder of an archbishop was a shocking event. The next day, Ælfheah’s body was taken to London for burial in St Paul’s cathedraclass="underline" he was immediately recognised as a martyr. Once the gafol was paid and shared out, the Danish army split up. Most headed home with their loot, but Thorkell entered Æthelred’s service with forty-five ships, promising to defend his kingdom in return for which he and his men would be fed and clothed. To cover the costs Æthelred introduced an annual land tax called the heregeld (‘army-tax’). Like many taxes introduced as a temporary expedient, the heregeld became permanent and was not officially abolished until 1052. Thorkell’s decision is sometimes presented as being motivated by remorse for Ælfheah’s murder, but putting his army up for hire was probably a commercial decision: in 1014 Æthelred paid him 12,000 pounds (5,443 kg) of silver raised by the heregeld.
Back in Denmark, King Svein must have watched Thorkell’s growing wealth and influence with suspicion. What might he do if he returned to Denmark with a ship full of treasure and a loyal army at his back? It was scarcely credible that he would just retire quietly to his family estates. Svein must also have been well-acquainted with the chaotic condition of England’s defences and, as there was no shortage of experienced warriors now that most of Thorkell’s army had come home, he decided that the time was right for him to launch a new invasion on his own account. This time, however, he was planning to conquer England.
In the high summer of 1013, Svein’s fleet landed at Sandwich and then followed the coast north, round East Anglia and into the Humber estuary, then up the River Trent to Gainsborough, where he made his headquarters. There the Northumbrians and the Danish settlers of the Danelaw submitted to him and gave hostages. Svein left the hostages and the fleet in the care of his son Cnut at Gainsborough, took horses and set off south plundering and burning as he went. Town after town submitted. Only at London did Svein meet resistance.
The Londoners had already seen off Olaf Tryggvason and several attacks by Thorkell’s army. Now with Æthelred and Thorkell inside the city walls, Svein’s army also failed to break through. London was not yet England’s capital – Winchester in Hampshire was the Wessex dynasty’s main political centre – but it was by now its largest and most prosperous city. Though the Vikings sacked London a number of times in the ninth century, they indirectly helped set the city on the road to national pre-eminence. After he seized control of London in 886, Alfred the Great rebuilt the old Roman walls and installed a garrison. New streets and wharves were built and the trading community at Lundenwic (at Aldwych) was relocated within the protection of the walls. Around 915 another fortified settlement was founded on the south bank of the Thames at Southwark. It was probably around this time that London Bridge was built, not just to link both sides of the river but also to control shipping and prevent hostile fleets sailing up the river. In this way London became critical to the defence of the kingdom against the Vikings.
Repulsed from London, Svein headed west to Bath, where the nobles of Wessex submitted to him. London, now the only place that still had not recognised Svein as king, bowed to the inevitable, submitted and gave hostages. Svein returned to Gainsborough and demanded that the English pay and feed his army. Æthelred took refuge with Thorkell and his army at Greenwich on the Thames. He then went to the Isle of Wight, where he spent Christmas before going into exile with his brother-in-law Duke Richard in Normandy. Svein did not enjoy his victory for long. He fell ill and died at Gainsborough at Candlemas, 3 February 1014. The Danish army elected Cnut as king, but the English recalled Æthelred from exile with a message saying ‘that no lord was dearer to them than their natural lord, if he would govern them more justly than before’.
Come Easter, Cnut was still at Gainsborough. The people of Lindsey, a Danish-settled district of Lincolnshire, agreed to supply Cnut with horses and join him on campaign. However, Æthelred behaved with uncharacteristic decisiveness and marched north before Cnut was ready. Cnut took to his ships and abandoned the people of Lindsey to savage retaliation. Cnut sailed south to Sandwich, where the hostages who had been given to his father were put ashore, but only after their hands, ears and noses were cut off. Returning to Denmark, Cnut found that his brother Harald had been made king. Harald refused Cnut’s request to divide Denmark with him but did agree to help him conquer England.
Æthelred soon showed that he would not govern his people any more justly than before. At the assembly at Oxford in 1015, ealdorman Eadric murdered two thegns from the Five Boroughs, Sigeferth and Morcar, so that the king could seize their property. Before that happened, Æthelred’s eldest son, the atheling (crown prince) Edmund Ironside, rebelled, married Sigeferth’s widow and seized the properties for himself. Edmund’s motive was probably to forestall a claim on the throne by his younger half-brother Edward. While this dispute was going on, Cnut arrived back at Sandwich with a very large fleet. Writing very shortly after Cnut’s invasion, the German chronicler Thietmar of Merseburg (d. 1018) gives the strength of the fleet as 340 ships, each with eighty men, which adds up to a force of 27,200 men. Viking armies of this size are not credibly attested elsewhere but, while Thietmar’s numbers are almost certainly exaggerated, it is likely that Cnut’s army was impressively large by the standards of the day. This time Cnut had some heavyweight allies, jarl Erik of Lade (Hlaðir) (d. c. 1023), the most powerful magnate in Norway, and Thorkell the Tall, both of whom could raise large armies in their own right. Thorkell had decided that it was time to patch things up with Cnut and had travelled to Denmark during the winter to offer to serve him with his army. With the fate of a kingdom at stake, Cnut’s army attracted warriors from all over Scandinavia, not just Denmark.