During this period, as in others, many Greek cities could not produce enough food from their territories for the ever-growing populations within their city walls. Consequently some basic foodstuffs such as grain had to be imported on a large scale from abroad. The Greeks’ answer to these problems was to establish trading posts and settlements across the Mediterranean and beyond.

The first were in Ionia, on the west coast of modern Turkey, and in the Near East. Others were established later around the Black Sea and the Mediterranean, particularly in southern Italy. Each colony was sponsored by a wealthy city such as Corinth, Euboean Eretria and Chalkis, and Ionian Miletus. They organised and paid for fully-equipped expeditions that built and populated new city-states. Colonies were modelled on Greek cities and in this way Greek culture and life spread abroad.

The colonies were usually founded at places with good farmland and natural harbours that were adjacent to non-Greek peoples who were friendly and willing to trade. Colonies on the Black Sea such as Olbia traded with the Scythians for south Russian grain. At Massilia (modern Marseilles) merchants traded with the local Celtic population and further north with Germanic peoples. Greek merchants traded widely and acquired important commodities such as metals and grain.