Thucydides' History of the Peloponnesian War is an intensely personal and a tragic work. A careful reader feels this from the very first sentence: ‘… I began writing the History from the moment the War broke out; I expected it to be a great war and more worth a λόγος than any war that had preceded it.’ This tone is maintained throughout the work. Even if we leave aside the dozens of personal judgements in the History, its intensity of feeling everywhere reminds us of Thucydides' personal involvement.

We learn from ancient criticism that Thucydides was admired as the historian of πάθος, as opposed to Herodotus, the historian of ἦθος. The sense of the tragic, which exists as a fine suffusion in parts of Herodotus' work, dominates the whole History of Thucydides. This sense of the tragic is something quite different from the clinical objectivity which has been so often, and often so thoughtlessly, ascribed to him. His very reluctance to speak of himself, his way of stating all as an ultimate truth, is, if we must use the word, one of his most subjective aspects. When you can say, ‘so-and-so gave me this account of what happened, and it seems a likely version’, you are objective about your relation to history. But when, without discussing sources, you present everything as αὐτὰ τὰ ἔργα (1. 21. 2), the way it really happened, you are forcing the reader to look through your eyes, imposing your own assumptions and interpretations of events.