Rasmusen Weblog

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Harpagos having marched his army against them began to besiege them, at the same time holding forth to them proposals and saying that it was enough to satisfy him if the Phocaians were willing to throw down one battlement of their wall and dedicate one single house.[164] But the Phocaians, being very greatly grieved at the thought of subjection, said that they wished to deliberate about the matter for one day and after that they would give their answer; and they asked him to withdraw his army from the wall while they were deliberating. Harpagos said that he knew very well what they were meaning to do, nevertheless he was willing to allow them to deliberate. So in the time that followed, when Harpagos had withdrawn his army from the wall, the Phocaians drew down their fifty-oared galleys to the sea, put into them their children and women and all their movable goods, and besides them the images out of the temples and the other votive offerings except such as were made of bronze or stone or consisted of paintings, all the rest, I say, they put into the ships, and having embarked themselves they sailed towards Chios; and the Persians obtained possession of Phocaia, the city being deserted of the inhabitants.

That is a hugely important point. Most of a society's wealth is its people and its moveable goods, especially in a primitive society where land is plentiful. Today, about 2/3 of wealth is in human form, and a good bit of the rest is chattels, moveable property. With enough boats, the Phocaians could escape with perhaps 90% of their wealth-- or, put differently, the Persians could only conquer 10% of it.

It would be much harder for non-maritime people to escape conquest in this way, but still possible.

Consider the implications for how badly conquerors could treat their subjects. If your subjects can run away with 90% of their wealth, this means you had better not try to impose taxes at a rate higher than 10%. Did the Persians keep to that limit, with the Ionians and other maritime subjects?