History of the Peloponnesian War (1.3.4-1.5.1)

However this may be, those who then received the name of Hellenes, whether severally and in succession, city by city, according as they understood one another's speech, or in a body at a later time, engaged together in no enterprise before the Trojan war, on account of weakness and lack of intercourse with one another. And they united even for this expedition only when they were now making considerable use of the sea.

Minos is the earliest of all those known to us by tradition who acquired a navy. He made himself master of a very great part of what is now called the Hellenic Sea, and became lord of the Cyclades islands and first colonizer of most of them, driving out the Carians and establishing his own sons in them as governors. Piracy, too, he naturally tried to clear from the sea, as far as he could, desiring that his revenues should come to him more readily.

It should be explained that in early times both the Hellenes and the Barbarians who dwell on the mainland near the sea,[*] as well as those on the islands, when once they began more frequently to cross over in ships to one another, turned to piracy, under the lead of their most powerful men, whose motive was their own private gain and the support of their weaker followers, and falling upon cities that were unprovided with walls and consisted of groups of villages, they pillaged them and got most of their living from that source. For this occupation did not as yet involve disgrace, but rather conferred something even of glory.