Treece wrote several juvenile historical novels, some set during the Viking Age, and this trilogy is regarded as among his best.
He has a complicated series of adventures which takes him to a giant's treasure cave in Ireland, then Jebel Tarik (Gibraltar), then to Miklagard (the Norse name for Constantinople) where he joins the famous Varangian Guard.
Eventually Harald returns home to Norway via the great ship-portage on the Dnieper.
Harald is now a mature man who enjoys a peaceful life of farming with his wife and sons.
Significant scenes include the death of one of the raiders, Havlock Ingolfsson, whom Harald abandons to die on a skerry, and Harald's death at the hands of Heome, the mad handless brother of heroic Wawasha.