When ancient historians wrote their works, were they concerned about telling the truth or telling a story? What methodologies did they follow? Why did the ancient historians omit certain information or lie? The Bryn Mawr Classical Review has a review of Luke Pitcher’s, Writing Ancient History: An Introduction to Classical Historiography which looks into these questions. One point the review mentions is a different form of writing history.

One theme to which the book continually returns, and which Pitcher treats more fully here, is that the limits of historical writings cannot easily be pinned down, and can take multiple forms, and that there are many ways to engage with the historical past. Sometimes the lines between history and fiction, for example, were blurred, and that the ‘action of the swan’ means that it is not always possible for us as modern readers to understand the nature of the texts we are dealing with.
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He brushes over the poetical and mythologically rooted ‘histories’ which continued to exist beside other prose and ‘factual’ ways of thinking historically; but it is significant for our understanding of historical writing (in Greece at least) that it emerged from different kinds of historically minded traditions.[Bryn Mawr Classical Review 2010.07.12]

A good example of a myth turning into reality was the Trojan war. Interested in the location of Homer’s Troy, Heinrich Schliemann started digging for it in Turkey. Though British archaeologist Frank Calvert had identified Hissarlik as the site of Troy, his work was over shadowed by Schliemann who published Ithaka, der Peloponnesus und Troja in which he claimed Hissarlik as the site of Troy. This is now accepted by historians.