The title does justice to the content of the book: it is a dispassionate and detailed historical account of the conflict between Athens and Sparta, which took place in the years 431-404 BC, and which extended from all over Greece, to Sicily, all the towns of the Ionian Sea, reaching as far as the Hellespont (Bosphorus Strait and the Dardanelles). Initially limited to a conflict between two cities, they attracted allies and created two sides: the whole area had to side with one or the other, unable to remain neutral.
The author was a “stratego” (general) in the service of the Athenians, who, through an error of command, was banished by his people; in a neutral position, he followed the war in detail. It is noted that the book is truncated: the war lasts until 404 B.C.; but the account ends in 411 B.C., without explanation. The date of composition is unknown, after 404 BC.
The care with which he writes is remarkable: from the beginning the author declares that he wants the truth, and seeks to document himself, and to relate only the facts. The speeches of those responsible are compiled in their entirety.
In the book we see that the Greek world has a common culture: the organization of the city; religion; the army, the navy; the ideals of honor and virtue; trying to argue, discuss, convince; the ideal of justice, which during the war gives way to utilitarianism.
Thucydides accepts as acceptable the various political systems in force at the time (monarchy; democracy; oligarchy; limited democracy, with oligarchic regime). However, in the field of external action, Thucydides is an imperialist: the stronger must dominate the weaker; justice is only applicable between equals, not for the weak. This pragmatic idea led in the book to the progressive revolt of the Greeks subdued by Athens, and persisted in history.
Great book on the history of the Greek world at this time, very enjoyable to read.