The book is set in the late 10th century & follows the adventures of Orm ("serpent"), called "Red" for his hair & his temper, a native of Scania. The story portrays the political situation of Europe in the later Viking Age, Andalusia under Al-Mansur Ibn Abi Aamir, Denmark under Harold Bluetooth, followed by the struggle between Eric the Victorious & Sweyn Forkbeard of Denmark, Ireland under Brian Boru, England under Ethelred the Unready, the Battle of Maldon, all before the backdrop of the gradual Christianisation of Scandinavia, contrasting the pragmatic Norse pagan outlook with Islam & Christianity.