Appian's theme is the process by which the Roman Empire achieved its contemporary prosperity, and his unique method is to trace in individual books the story of each nation's wars with Rome up through her own civil wars. Although this triumph of "harmony and monarchy" was achieved through characteristic Roman virtues, Appian is unusually objective about Rome's shortcomings along the way.

Of the work's original 24 books, only the Preface and Books 6-9 and 11-17 are preserved complete or nearly so: those on the Spanish, Hannibalic, African, Illyrian, Syrian, and Mithridatic wars, and five books on the civil wars.

This edition of Appian replaces the original Loeb edition by Horace White and provides additional fragments, along with his letter to Fronto.