The story takes place after the Roman legions leave Britain. There are several High Kings who are nominally in charge of newly forming tribal kingdoms.

Vortigern, the High King, gives Kent to his Saxon allies. Other Saxons seize neighbouring Sussex.

Aurelius Ambrosius defeats Vortigern and, as High King, tries to drive out the Saxons, but settles for a treaty.

Owane Thantgwyn (bright teeth), nicknamed Arth (meaning The Bear), marries Ganumara and they become King and Queen of Powys. The Arth (Owane) with his perfect guards and fast-moving mobile cavalry, bring an end to the developing chaos.

Merion ap Eugene, a young man in Coccium (Cocha), works mostly leading a packhorse train for his father throughout the north selling sulphur, salt, iron and coal.

Merion fights off Gaelic brigands and comes to the attention of Owane. Riding with Owane’s cavalry, Merion fights the Gaels around Chester.

Merion returns to Cocha, resuming his role as a packhorse leader in the family business.

The Gaels turn their attention to the fertile land west of Cocha. Merion is sent south to Vironconium to appeal to Arth for help.

There is a meeting of kings and Merion meets Aurelius Ambrosius, the High King, and the great men of Britain.

Merion joins Owane’s force and they head south to aid Aurelius fight a large force of Saxons near Bath. Aurelius and Arth win a great victory. Merion is sent back to Viroconium. En-route he meets Bronwen and finds love.

Arriving at Viroconium he is given a force of raw cavalry and sent home to fight the Gaels. Owane, then Aurelius, join him in fighting the Gaels.

Finally, Merion is free to go back to find Bronwen.