For decades an enigmatic three-mile-long wall in the countryside outside ancient Athens has perplexed archaeologists and historians. When was this structure, known as the Dema wall, built, and what role did it play in Greek military history? In a tour de force of archaeological and historical argument, Mark H. Munn establishes the place of the Dema wall in the defense of Athens and offers a completely new perspective on the Boiotian War (378-375 B.C.), in which the Athenians and their Theban allies defended themselves against an overwhelming Spartan army. Building on the archaeological evidence for Athenian preparedness, Munn demonstrates that Athens played a decisive role from the beginning of the Theban uprising against Sparta, an uprising that set in motion events eventually leading to the downfall of the Spartan empire.

Though Theban and Athenian plans were almost thwarted by the Spartans, the Athenians secured their ascendancy through a boldly innovative defense strategy, the heart of which was the Dema wall. For those who have seen it, the Dema wall demands an explanation. A monumental work, the barrier wall closed a key pass into the plain of Athens against an invader from the west. Since no ancient reference to it survives, scholars have contested the date and purpose of the wall's construction, placing it anywhere between the Geometric Age and Hellenistic eras, as part of the general defense perimeter around Athens.

By 1979 the growth of modern Athens threatened to destroy the wall; quarries and a city dump surrounded it. This endangerment prompted the Greek Archaeological Service to invite Munn to direct the excavation of a watchtower above the wall. Skillfully combining evidence from his archaeological fieldwork with historical arguments, Munn demonstrates that the Dema wall was erected as a military obstacle to Spartan invasion on the specific occasion of the Boiotian War, and that its presence affected not only the strategy of the Spartan generals, but, ultimately, the outcome of the war. In The Defense of Attica, the Boiotian War becomes, for the first time, the focus of a modern work. Munn treats the reader to a lively and absorbing narrative account of this episode. His vivid descriptions and effective use of extracts from literary sources bring opposing generals, military tactics and battle scenes to life.