Samos is a Greek island, situated just off the Asian coast, close to Miletus. This was a Greek city too, but it belonged, like the other towns of Asia Minor, to the realm of the Lydian king Croesus. When this rich ruler was defeated and killed in c.547 by the Persian king Cyrus the Great, Lydia was incorporated in the Achaemenid empire. The Persian general Harpagus subdued the towns of the "Yaunâ", and the political situation in the rest of the Greek world changed considerably. There was some turmoil on Samos, and in 540, three brethren, Polycrates, Pantagnostus, and Syloson, executed a coup d'état. Supported by many citizens who could afford a panoply, they captured the citadel of Samos.
The first-mentioned had the second executed and expelled the youngest, Syloson, who went to Persia. From now on, Polycrates was sole ruler, or, to use the Greek term, tyrant. He seems to have been a popular man, who did not need to change the constitution to control the state. On the other hand, those opposed to his reign, typically members of the old aristocracy, were either sent into exile or voluntary left the island. The most famous was the philosopher Pythagoras, who went to Egypt and southern Italy; others settled in Dicaearchia (modern Puteoli near Naples).
Among Polycrates' first acts was the fortification of the city of Samos, which can archaeologically be dated to the third quarter of the sixth century. To this project belonged two others: an aqueduct and a mole that was to protect the port. These buildings were designed by a man named Eupalinus.
Like other tyrants, Polycrates tried to improve the quality of life for his people. Samos prospered and Polycrates could show this by building a large temple, which he dedicated to Hera. Together with the wall, mole and aqueduct, the sanctuary was reckoned among the greatest feats of engineering. The philosopher Aristotle of Stagira even compared them to the pyramids.
Many scientists and scholars visited the Samian court: for example, physician Democedes, the poets Anacreon and Ibycus, and the already mentioned architect Eupalinus.
The Persians did not show much interest in the conquest of the islands in the Aegean Sea. They were warriors, not sailors. On the other hand, the Egyptian king Amasis (Egyptian name Khnemibre Ahmose-si-Neit), fearing a Persian attack, had developed a naval strategy. As long as he and his allies controlled the waves, king Cyrus was unable to attack the country of the Nile, because any invader would have to pass along the waterless northern coast of the Sinai desert, where his army would be vulnerable. So, the pharaoh built a navy, hired Carian and Greek mercenaries, conquered Cyprus, and allied himself to Polycrates. He gave him large amounts of money, which the Samian used to build a navy of no less than 100 ships, each with 50 rowers and 10 archers. This cost one talent a day, or 7-8 tons of silver per year. In the sixth century, this was a very large sum.
Egypt's defense was now partly in the hands of the Samians, which made Amasis' kingdom vulnerable. We do not know what went wrong, but after the death of Cyrus in 530, Polycrates decided to switch sides and join the new Persian king Cambyses. This is told by the fifth-century Greek researcher Herodotus of Halicarnassus:
Without the knowledge of the Samians, Polycrates sent an envoy to Cambyses the son of Cyrus (who was gathering an army to attack Egypt) and asked him to send a messenger to him in Samos to ask for an armed force. When Cambyses heard this, he sent an envoy to the Samians and requested a naval force to join him in the war against Egypt. So Polycrates selected those of the citizens whom he most suspected of desiring to rise against him, and sent them away in 40 warships, charging Cambyses not to send them back.note[Herodotus, Histories 3.44.]
It must be noted that the admiral of the Egyptian navy, Wedjahor-Resne, at the same moment also changed sides, so it is possible that Cambyses prepared his Egyptian expedition by bribing away Amasis' naval allies.
Ultimately, this was to be Polycrates' undoing. After the fall of Egypt in 525, he had no financial support any more. Samian rebels, assisted by armies from Sparta and Corinth, invaded the island, and Polycrates found himself in a tight spot. However, the walls of Eupalinus were strong and the tyrant survived. But without capital, he remained vulnerable.
In March 522, civil war broke out in the Persian empire. The usurper Gaumâta revolted against Cambyses, who died before open war broke out. During the summer, Polycrates was invited by the satrap of Lydia, Oroetus, to come to Sardes. Herodotus quotes the message:
I understand, Polycrates, that [...] your resources are not equal to your designs. I have a proposal to make which, if you adopt it, will ensure your success - and my own safety, for it is clear from reports I have received that [the Persian king] is plotting my death. Come, then, and get me out of the country; I promise you a share in everything I possess, and that will give you enough money to get control of the whole of Greece. If you have any doubts about my wealth, send whoever it is you must trust, and I will show him what I have.note[Herodotus, Histories 3.122; tr. Aubrey de Selincourt.]
Polycrates, who was, in Herodotus' words, 'very fond of money', decided to visit Oroetus. According to Herodotus, Polycrates' daughter had a terrible nightmare, in which she saw how her father was washed by the god Zeus and anointed by the Sun.
Somehow or other - the precise manner need not be told - Oroetus had him murdered, and the dead body hung on a cross. [...] The dream of Polycrates' daughter was thus fulfilled by his crucifixion: when rain fell, he was washed by Zeus, and he was anointed by the Sun when under the sun's heat the moisture was sweated out from his body. This, then, was the end of the long-continued prosperity of Polycrates.note[Herodotus, Histories 3.125.]
When the chaos in the Persian empire came to an end - Gaumâta was killed and succeeded by Darius the Great - the Persians restored order. Oroetus was executed and Samos was given to Polycrates' brother Syloson.note[The story of Syloson's cloak is told here.]
Polycrates soon became a moral example. Herodotus tells a very famous story about the Samian tyrant, who was so blessed by the gods that even when he threw a precious ring into the sea, a fisherman would catch the fish that had swallowed the object. His ally Amasis understood that a man who was so lucky would one day be punished by the gods, who are envious of human happiness. And this was, to the pharaoh, sufficient reason to end the alliance. In fact, it seems to have been the other way round -Polycrates terminating the alliance- but the moral point was there.