History of the Peloponnesian War (1.3.4-1.5.1)

It appears therefore that the several Hellenic communities, comprising not only those who first acquired the name, city by city, as they came to understand each other, but also those who assumed it afterwards as the name of the whole people, were before the Trojan war prevented by their want of strength and the absence of mutual intercourse from displaying any collective action.

Indeed, they could not unite for this expedition till they had gained increased familiarity with the sea.

And the first person known to us by tradition as having established a navy is Minos. He made himself master of what is now called the Hellenic sea, and ruled over the Cyclades, into most of which he sent the first colonies, expelling the Carians and appointing his own sons governors; and thus did his best to put down piracy in those waters, a necessary step to secure the revenues for his own use.

For in early times the Hellenes and the barbarians of the coast and islands, as communication by sea became more common, were tempted to turn pirates, under the conduct of their most powerful men; the motives being to serve their own cupidity and to support the needy. They would fall upon a town unprotected by walls, and consisting of a mere collection of villages, and would plunder it; indeed, this came to be the main source of their livelihood, no disgrace being yet attached to such an achievement, but even some glory.