"I will examine the writers of Hellenica: Thucydides, Xenophon, the anonymous author of the Hellenica Oxyrhynchia, Ephorus-Diodorus, Theopompus, Cratippus, Callisthenes to understand the different “historiographical tendencies during the period of Spartan hegemony”, during the last phase of the Peloponnesian war and the forming of Spartan supremacy (from 412 to 386 B.C.) . By identifying the historiographical perspective of the author of the Hellenica Oxyrhynchia, re-examining Diodorus and Ephorus’ fragments, I will be able to study Diodorus in his own right against the traditional view that he was solely a compiler of earlier works. This will help to clarify his relation with the Hellenica Oxyrhynchia. I will also investigate the style and method of composition of the writer of the Hellenica Oxyrhynchia, in order to identify the relation between the Anonymous and Theopompus, to clarify of which Greek City-States the author of the Hellenica Oxyrhynchia knew the inner political debate, to analyse the Hellenica Oxyrhynchia and the so-called Theramenes Papyrus, commonly considered a political pamphlet, in order to find out if they come from the same author.In the fourth century B.C. the writers of Hellenica, realising that new political powers were growing, extend their subject matter to Macedonian and Persian history and contemporary oratory to discuss some crucial themes of the relation between Greeks and ‘the others’ (Macedonians and Persians). Therefore, the question is to understand to what extent the main topical themes of oratory influenced historiography and whether historiography, for its part, had a role in the formation of political ideas (oratory) during the period of Spartan hegemony. This is a new approach to clarify this phase of Greek history, to better understand and define the conception of ‘Greek identity’ and Greek perception of ‘the others’ and of their physical world, as well as of Greek physical world."