The novel is a retelling of the assault on the Roman Republic by the Carthaginian general Hannibal. It begins in Ancient Spain, where Hannibal sets out with tens of thousands of soldiers and 30 elephants. After conquering the Roman-allied city of Saguntum, Hannibal accepts Rome's declaration of war. He befriends peoples disillusioned by Rome and outwits the opponents who believe the land route he has chosen is impossible. Hannibal’s troops suffer brutal losses as they pass through the Pyrenees Mountains, ford the Rhone River, and make a winter crossing of the Alps, before descending to fight battles at the Trebia River, Lake Trasimene, Cannae and Zama. The novel ends roughly where the war ends, although Hannibal lived on for some years as both a political figure and a mercenary soldier.