The Greek city states sold their surplus goods by trading with each other and with other lands around the Mediterranean and Black Seas. There were no large trading companies. Each merchant usually had his own ship. Some traders were rich enough to finance their own deals, but many had to borrow from bankers. In Athens, many of the richest traders were metics (foreigners). They were forbidden by law to own land, so many invested in trade abroad. The Greeks travelled far in search of trade. The goods were usually sent in sailing ships. To navigate, they used the stars and well-known landmarks. The main exports from Greece were wine, olive oil and manufactured goods, such as cloth, pots and statues. Imports included grain from the Black Sea, copper, tin, timber and goods from Africa and the East, such as ivory, incense, spices, perfume, silk and slaves.
At the time of the Dorian invasions, many people left Greece and set up colonies in ionia, on the west coast of what is now Turkey. The next wave of colonization began in the 8th century BC. A rise in population had led to a serious shortage of farming land and many left to seek their fortunes abroad. Families of emigrants set off with animals and supplies of food and seed for planting. They settled in largely uninhabited areas and built new cities, modelled on the Greek ones. The new cities provided raw materials and markets for Greek goods. They were completely independent, though fellow Greeks sometimes came to their aid when they were threatened by enemies. A tribe called the Graii settled in Italy. The Romans later called them Graeci. This word came to be used for all who spoke their language, and from it comes out the word "Greek".