There may be no more difficult thing to write than an historical novel, with its judicious balance of fact and fiction. Some – one thinks of Robert Graves (of «I Claudius» and «Claudius the God») and Mary Renault (of «The King Must Die») – are so thoroughly steeped in their time that the present peels away to reveal that other country that is the past, rendering it both utterly strange and wholly familiar. Others, less ambitiously, set themselves the task of creating exciting adventures set in the past that blend fictional characters and factual events. Yet others recreate legends, giving explanations of the mistiest of times. Alice Leader’s second novel, «Shield of Fire» (Puffin 2004), a fictional recreation of the Battle of Marathon (490 BC), is sparked by one of Herodotus’ more throwaway passages. «The Alcmaeonidae [a noble Athenian family] were accused,» wrote the Father of History, of having «an understanding with the Persians, and made a signal to them, by raising a shield, after they [the Persians] were embarked in their ships.» This was just after the battle, in which the Athenians and their allies, the Plataeans, routed the Persians who had landed on the plain of Marathon, by charging them at a dead run. Historians have been arguing about the battle ever since. Leader takes up the gauntlet. That mysterious signal, the raised shield (hence the title), is the starting point for her book. Prefacing it is a quote from Herodotus (Book VI ): «It is impossible to deny that a shield was used to make a signal, but I can add nothing beyond what I have already said on the matter of who the signaler was.» It is Leader who does the adding. The story begins, not in Athens, but on Thera in 492 BC, where Nyresa, a young girl who lost her mother young, lives with her grandmother. The only two shadows on her life are recurrent nightmares of earthquakes and the growing menace of Persian domination. For the Therans, the question is whether to give bread and water, the Persian form of submission, or resist. To answer this troubling question, Nyresa’s priestess-grandmother goes on a pilgrimage, leaving the girl with relatives in the wealthy and powerful city of Athens. There, she makes friends: her crippled cousin Rhode, her patrician friend Agariste, and Klio, an Aeginetan flute girl. But it is the 17-year-old Cherson, who works for a blacksmith while trying to get acknowledged as the nephew of Miltiades (the Athenian general at Marathon), that captures her heart. However, there is treachery afoot. Agariste’s brother and cousin are scheming with the exiled tyrant Hippias in the Persian camp to restore oligarchic rule. How the girls hatch a plot to foil them, how Nyresa finds her destiny and the reason for her troubling nightmares and how the Athenians beat the Persians at Marathon is the subject of the rest of the book. Leader is obviously keen on the subject and has done extensive research. She follows Herodotus closely, especially in the battle scenes, which, seen from Cherson’s point of view, are vividly described. The book is packed with detail about life in ancient Athens, scenes of the Agora, religious rituals, and careful descriptions of objects and artifacts. Occasionally she stumbles over minor details. Running through the Agora, Nysera eyes a stall covered with peppers. Peppers? Weren’t peppers introduced from South America after Columbus’s time? (A mention of eucalyptus trees further on is another botanical incongruity.) Should the book (soon to come out in a French version as well, published by Gallimard) be translated into Greek, these incongruities may strike readers who have had exposure to ancient Greek history. Otherwise, this is a well-reasoned-out account of the Battle of Marathon (Herodotus leaves us with more questions than he answers) that will give children an easy introduction to some of the issues surrounding it.