History of the Peloponnesian War

But by land no wars arose from which any considerable accession of power resulted; on the contrary, all that did occur were border wars with their several neighbours, and foreign expeditions far from their own country for the subjugation of others were not undertaken by the Hellenes. For they had not yet been brought into union as subjects of the most powerful states, nor, on the other hand, did they of their own accord make expeditions in common as equal allies; it was rather against one another that the neighbouring peoples severally made war.