It tells the story of Hereward, a historical Anglo-Saxon figure who led resistance against the Normans from a base in Ely surrounded by fen land.

He sets off to see the world and considers such options as the Vikings of the northern seas, the Irish Danes or service with the Varangian Guard in Constantinople.

William of Normandy leads a host of mercenaries against Ely but is repulsed with heavy losses when the English set fire to the surrounding reeds.

In spite of that victory, Hereward's resistance is worn down by the Norman invaders and the intrigues of the Countess Alftruda, who separates the hero from Torfrida.

[1] It is believed to have been read and used as a source of inspiration by J. R. R. Tolkien; verbal echoes include the use of "horse-boy" and the verb "ruffling", as well as Kingsley's mention of "orcs" in a list of monsters.