The enemy is massing on the borders, a united force for once. The king, a man of many victories, is in failing health, and his heir is an untested youth. Uhtred, the king's champion, leads his country's forces to war, but his victory is soured by personal tragedy and by the envy of the king's court. So he breaks with the king and takes off for the land of his birth, determined to resist all calls for his return. That is, until one unexpected request... This is the making of England brought magnificently to life by the master of historical fiction.
The second major campaign of King Alfred against the invading Danes begins in earnest. Uhtred of Bebbanburg is now the preeminent warlord of Wessex, Alfred's kingdom. Alfred refers to him as "my dux bellorum, my lord of battles." Alfred urges him to swear to serve Alfred's son and presumed heir, Edward. "Scour the enemy from England," Alfred says, "and make my son safe on his God-given throne."
Uhtred is unwilling to make that commitment. He has long wanted to return to his family's stronghold at Bebbanburg in Northumbria and to deal with his uncle Ælfric, who stole the family properties and titles from him. He wants his obligation to Alfred and Wessex to end when Alfred, now seriously ill, passes away.
Uhtred is military governor of Lundene (London), sharing power with Bishop Erkenwald, whom he dislikes but respects. At Alfred's behest, Uhtred delivers a message to the Danish Jarl (earl) Hæsten, whose fleet threatens Wessex, that Alfred will pay a large ransom for Hæsten to leave. Alfred cannot attack Hæsten, because another Dane, Jarl Harald Bloodhair, has attacked at Cent (Kent). Hæsten and Alfred reach an accord, and Hæsten leaves hostages and accepts missionaries. Though he did not, Hæsten's wife and family undergo baptism, which plainly amuses Hæsten, like everything else.
Uhtred knows that the hostages are fake and that if Harald defeats Alfred, Hæsten will attack Wessex. While travelling with a small force to meet Alfred, Uhtred captures Skade, Harald's woman. Skade is a formidable fighter in her own right, and leads one of Harald's war parties. She and her party are captured while raiding a village in Eastern Wessex. Harald approaches Uhtred leading a line of Saxon captive women, and threatens to kill all of them if Skade is not returned to him. After he butchers one woman in front of her child, Uhtred releases Skade to him. Skade curses Uhtred as she and Harald make their escape.
At a meeting with Alfred and his advisers, Uhtred urges the king to adopt a plan to lure Harald to Farnham by sending a modest force there, and then attack Harald from the rear with most of Alfred's troops when he takes the bait. The plan works brilliantly. Uhtred and his men defeat Harald's forces and again take Skade prisoner. Harald is severely wounded, but escapes to Torneie Island (Thorney Island). There, with a few followers, he is able to use the island's natural defences and a palisade he builds to repel later attempts to defeat him. However, he is trapped there.
While celebrating the Mercian/Saxon victory at Farnham, Uhtred is devastated by news that his beloved wife, Gisela, has died in childbirth, along with the child she bore. When Uhtred and Skade return to Lundene, Alfred's advisor, Bishop Asser uses the mad brother Godwin to denounce Gisela's name, ranting that Gisela was the devil's whore, and has come back from the dead as Skade. Uhtred flies into a rage and kills Godwin accidentally. Uhtred retreats to his house, where Uhtred's old friend and mentor, Father Beocca, tells him that Alfred has ordered Uhtred to pay a huge fine and swear an oath to Alfred's son Edward the Æthling. Alfred holds Uhtred's children as hostage to his terms, and places them in the custody of Æthelflaed, Alfred's daughter and wife of Æthelred, the ealdorman of Mercia. Furious, Uhtred reneges on his oath to Alfred and sails, with Skade, to Dunholm in Northumbria, stronghold of his old friend Ragnar, a Danish leader. Uhtred trusts Æthelflaed to protect his children.
Eager to use his newfound freedom and encouraged by Skade, Uhtred goes viking. He sails to Frisia to loot, kill and plunder Skirnir, Skade's husband, and on the journey, he and Skade become lovers. After he defeats and kills Skirnir, he is disappointed when Skirnir's treasure hoard fails to meet his expectations. When Skade demands half of the hoard as her share, Uhtred denies it to her. From that point on Skade becomes hostile to Uhtred. Uhtred winters at Ragnar's fortress at Dunholm.
During that winter, Brida, Ragnar's wife, convinces Ragnar to attack Wessex alongside the other Northumbrian Jarls, Cnut and Sigrid. During the meeting, Haesten arrives and declares that he will attack Mercia. Hæsten and Skade become infatuated with each other, and when Hæsten leaves, Skade goes with him. Uhtred is caught in a conflict of loyalties, between the Danes with whom he was raised, and his oaths to Alfred and Æthelflaed. He also fears for his children's safety, as they are in Mercia, in Æthelflaed's custody. His indecision is broken when his friend, the Welshman Father Pyrlig arrives. Pyrlig reminds Uhtred that he has given his oath to serve Æthelflaed, and 'oaths made in love cannot be broken'. Uhtred serves Æthelflaed. He first has to rescue her from Lord Aldhelm. Æthelred, Æthelflaed's husband, wishes to divorce her, to break free of Alfred's influence over Mercia. He directs Aldhelm to have sex with Æthelflaed, either by seduction, or failing that, by force. Either act would make her an adulterer, allowing Æthelred to divorce her. Uhtred kills Aldhelm, liberates Æthelflaed, and reunites with his children. He and Æthelflaed then go to Æthelred's council, surprising him before the assembled Mercian lords.
Warning of Jarl Hæsten's advance, Æthelflaed tries to win the Mercian lords to her side. She and Uhtred then wait at Lundene for support. Because Æhelred holds their purse-strings, none of the lords come, except for Lord Elfwold. Uhtred and Æthelflaed become lovers. Uhtred learns that Alfred had advised Æthelflaed to use Uhtred's oath to her to bring him back. Eventually, Edward Æthling arrives, along with Alfred's retainer and Uhtred's friend Steapa, and an army of twelve hundred of Alfred's best house troops. Uhtred again refuses to give his oath to Edward.
Thus reinforced, Uhtred marches ahead to Hæsten's two forts at Baemfleot (Benfleet), although Haesten is not there. Uhtred encounters and attacks a larger Danish force and is surrounded. He nearly loses the battle and his life, but is saved and the battle won by the timely arrival of Steapa and the rest of Alfred's troops. They capture the first of the forts. Uhtred makes preparations for the next battle and begins teaching Edward how to lead from the front. Uhtred assaults the fort and scales the ditch, using sails with ropes sown into them to provide sure footing on the slippery ditch. He tries to use ladders to get up the wall, but the first assault fails. His second assault ultimately succeeds after Father Pyrlig throws specially prepared beehives onto the walls. The bees distract the defenders so that Uhtred's force can scale the walls and capture the fort.
In the hall, Uhtred finds Skade and a hoard of gold. Harald Bloodhair, crippled and vengeful over Skade's betrayal with Haesten, suddenly appears, embraces Skade, and kills her at the same time. He then asks Uhtred to kill him. Uhtred does, then meets with Edward who says that he does not need Uhtred's oath as long as his sister has it. Uhtred and Æthelflaed then sail away from Baemfleot on the Thames.