Between 750 and 500 B.C., the Greeks founded colonies in many parts of the Mediterranean Basin and the Black Sea, beginning to exert their cultural influence, which remains in these regions to the present day. Around 730 B.C., permanent Greek colonies were established, based on the metals trade at Ischia and Pithecusai on the coast of Italy. Shortly thereafter, Corinth sent out agricultural settlers to Corfu (Kerkira) off the coast of northwest Greece and to Syracuse on Sicily. These settlements set the trend for the earliest colonization movement to the west. Southern Italy and Sicily became known as Magna Graecia (Great Greece) because of the extent and density of colonization that followed the initial ventures.

More than 150 colonies were established in Italy, along the coast of northern Greece, in the Bosporus, and on the Black Sea coast. The chief incentive for colonization was the need for additional land for agriculture and living space to accommodate population growth; colonies established by other civilizations, such as Miletus in Asia Minor, also challenged the Greeks to expand.