Le "Elleniche di Ossirinco", Diodoro e il problema storiografico dell'inizio dell'egemonia spartana

A careful reading of Diod., XIII, 8, 8 within its wider context shows that the counting of the 12 years of duration there ascribed to the Decelean War starts from 414/3 and consequently its end is 403/2. According to Isoc., XII (Panath.), 56, the Spartan hegemony lasted «scarcely ten years»; as the final year of this period is certainly the summer 394 (battle of Cnidus), its start must be placed in 403/2. There is further evidence that 403/2 has been seen as the watershed between the Peloponnesian War and the Spartan arche in a broad current of the post-Thucydidean historiography that has come down to the Trogus’ work (that is Justin’s Epitome). The historian of the Hellenica Oxyrhynchia too is likely to have joined, or perhaps inaugurated, this tradition: his choice of spring 402 as the beginning of the first year of the Spartan ascendancy (since most probably the «eighth year» in 12, 1 is 395/4) was only dictated, as already suggested by Eduard Meyer in 1909, by the seasonal chronology he had borrowed from Thucydides. The idea that the real close of the Peloponnesian War was the autumn of 403, when the demos came back to Athens after the dire parenthesis of the Thirty, was developed in the Isocrates’ circle and reflected a vision of the recent past in the light of the swift recovery of the Athenian power in the first decades of the IVth century BC.