The Siege of Winchester occurred in 911 AD when the Anglo-Saxon armies of Wessex and Mercia, led by King Edward the Elder and his sister Lady Aethelflaed, besieged the fallen West Saxon capital of Winchester, which had fallen to the Dyflin Viking lord Sihtric Caech. The Saxons launched several costly frontal assaults before finally breaching the gates with a smoke attack, but the captured West Saxon nobleman Uhtred of Bebbanburg succeeded in halting the fighting and allowing for the leaders of both sides to negotiate. Sihtric agreed to evacuate Winchester and leave Mercia, Wessex, and East Anglia in Saxon hands in exchange for Aethelflaed ceding Jorvik and the surrounding region of Northymbre to Sihtric's followers. This established a new peace between Saxon and Dane, one that would hold for years.
Background[]
In 911 AD, the Dyflin Viking lord Sihtric Caech - aided by the Mercian traitor Eardwulf - launched a surprise attack on the undefended West Saxon capital of Winchester while King Edward the Elder and his army were still at Aylesbury in Mercia, capturing his father-in-law Aethelhelm of Wiltshire, his Queen Aelfflaed, and his young son Aelfweard. Shortly after, the Viking lord Hastein captured the Queen Mother Ealhswith, Edward's illegitimate son Aethelstan, and Uhtred of Bebbanburg's daughter Stiorra at Thatcham in Berkshire and brought them to Winchester as a gift to Sihtric, his new lord. However, Uhtred and his band, who had been tied to a tree and left to die after Hastein left Thatcham, were freed by their companion Eadith, who had been cutting wood while they were captured. Uhtred sent Father Pyrlig to Kingsclere in Hampshire to warn King Edward that Winchester had fallen and that his mother, his Queen, his father-in-law, and both of his heirs had been captured. Edward, infuriated, ordered that the West Saxon and Mercian fyrds be raised, even sarcastically telling his men to raise the dead if they had to.
Meanwhile, Sihtric and his army fortified Winchester, preparing for a siege. The Danes were typically opposed to siege battles, but Sihtric had learned new strategies during his campaigns in Ireland and intended to test them on King Edward's army. His lieutenant Brida provoked Anglo-Saxon outcry when she had her men desecrate Christian burial sites around Winchester, and he personally made a statement of force when he publicly executed Eardwulf for being a man of excessive ambition. Meanwhile, he had the royal family kept prisoner near King Alfred the Great's tomb.
Siege[]

The arrow fire at Winchester
Soon after, Edward and his army arrived at Winchester, but Edward unwisely ordered his cavalry to charge into the city before the gate could close. Rather than charge out, the Danes instead shut and barred the gates and then rained heavy arrow fire onto the Saxon cavalrymen, inflicting heavy losses. King Edward then had his men pull back and warned the Vikings inside of Winchester that, by dawn the next day, the city would be surrounded, and he demanded that they surrender if they wished to avoid a massacre. Uhtred rushed up to the King and attempted to convince him not to fall for Sihtric's strategy, but the King ordered an attack when Sihtric did not respond to him. For the next thirty days, Edward's costly attacks failed, and he ultimately decided on a fire attack against the city. Upon hearing that his sister Aethelflaed had conquered York and forced the local Danes to submit to her, and was now headed south with her army, Edward was determined to expedite the cleansing of Winchester of the Danes. Upon hearing of the Saxon plans from Brida, Sihtric had Hastein gather clay and water and dampen the roofs to protect them from fire. Sihtric then presented Edward's captive sons and offered him the release of one of them if Edward would retreat, but, to prevent Edward from having to make the hard choice, Uhtred decided to trade himself for the two boys. Hastein convinced Sigtryggr to accept, as Uhtred was the only man capable of retaking the city. Sihtric secretly sought to bargain with Uhtred, angering Brida, who overheard these plans. She responded by throwing his sword from the walls, causing the Saxons to believe that he was dead.

The Saxon smoke attack
Shortly after, Aethelflaed and her army arrived from Northumbria, and she promised Edward to back any choice he made, even if it meant killing their own family by burning down the city. Aldhelm reminded them that Uhtred was within the walls, but Edward claimed that Uhtred was dead, and he then set about launching a surprise attack on Winchester under the cover of smoke (although Aldhelm warned him that a change of wind could blow the smoke back into the Saxons' eyes). When the Saxons dragged flaming bags towards the walls, the Danes poured oil onto them, causing the Saxons to be set alight by their own fires. They were also showered with arrows and rocks, and they again suffered heavy losses. Ultimately, however, the Danes began to be repulsed by the smoke, and the Saxons (aided by Uhtred's lieutenants) eventually made it to the walls with a wooden ram.

The final assault
When the gates were breached, Edward, Aethelflaed, and Uhtred's men led the attack on the Danish defenders, but, amid the fierce fighting, Uhtred convinced both kings to order shield walls so that they could negotiate, as Sigtryggr had a proposition. Ultimately, Aethelflaed reluctantly agreed to give Sihtric control of Jorvik in exchange for him promising not to enter Wessex, Mercia, or East Anglia, giving the Saxons control of three of the four kingdoms.
Aftermath[]
The Danes withdrew from Winchester without the need for a final assault, settling in their new lands in Northumbria, where Sihtric became King of Jorvik. Wessex, Mercia, and East Anglia were now confirmed as Saxon kingdoms, and there was faith on both sides that the peace would hold. However, Saxon nobles continued to vie for influence at Edward's court, and Aethelstan was sent to be raised by Uhtred in order to avoid a future civil war between him and his brother Aelfweard. Uhtred's daughter Stiorra was taken by Sihtric as part of the peace terms, but the two fell in love and eventually married.