The year is 655 and the great warrior king, Penda of Mercia, stands in a position of power, with allies in every kingdom, from the northern Pictish lands to the southern kingdom of the West Saxons, from the British states to the West, to East Anglia where its king now rules with his backing. Just one kingdom stands aloof, just one realm chafes against Penda's influence, Bernicia, ruled by Oswiu, the brother of the long dead Oswald of Northumbria, who, in the fourteen years since his brother's death, has failed to claim the combined Deiran and Bernician kingdoms for himself, but who schemes for a unified Northumbria, despite Penda's desire to truncate those wishes. As Penda and Oswiu align themselves for one more final battle of survival and supremacy, alliances will be made and broken, and the victory will go to the man most skilled in war craft and statecraft. Or will it? The ebb and flow of battle will once more redraw the lines of the petty kingdoms stretching across the British Isles.