During the Middle Ages Europe suffered from a scarcity of precious metals. Beginning in the middle of the 16th century, however, the American colonies, especially Mexico and Peru, loaded Spain with enormous qunatities of silver. Thus, this precious metal spread rapidly from one country to another, West to East, while the oriental goods that where a temptation to Europeans (spices, silk, and especially china) moved into Europe from the opposite direction, opening an intense trade on a world scale. The financial tool that favoured this trade development was a rough and heavy silver coin called a "real de a ocho", or "peso" in Spain, a "piece of Eight" in Anglo-Saxon countries and "piastra" in Italy. From Turkey to Persia, from India to China the "real de a ocho" became the most requested monetary unit and provided the liquidity necessary to make the intercontinental exchange system work. The exciting story of the Ibero-American silver trade and of the success of the "real de a ocho" are narrated in a skilfull manner by Carlo M. Cipolla.

Carlo M. Cipolla, former Professor of Economic History at the University of California at Berkeley. During his lifetime he also taught at several major Italian Universities.