This treaty was concluded at the end of the winter and the opening of spring immediately after the City Dionysia.The City or Greater Dionysia began before the vernal equinox and lasted several days. Just ten years and a few days had passed since the first invasion of Attica and the beginning of this war.

But one must reckon according to the natural divisions of the year, not according to the catalogue of the names of officials in each place, be they archons or others who in consequence of some office mark the dates for past events, in the belief that this method is more to be trusted; for it is really inexact, since an event may have occurred in the beginning of their term of office, or in the middle, or at any other point as it happened.