From Encarta
According to the most widely accepted theory, rice cultivation originated as early as 10,000 bc in Asia. Archaeological evidence shows that rice was grown in Thailand as early as 4000 bc, and over the centuries spread to China, Japan, and Indonesia. By 400 bc rice was cultivated in the Middle East and Africa. The invading armies of Alexander the Great probably introduced rice to Greece and nearby Mediterranean countries around 330 bc. Rice was brought to the American colonies in the early 1600s, and commercial production began in 1685. Rice cultivation, a very demanding process, has shaped values and changed history. For example, rice encouraged populations to crowd together to take advantage of a reliable food supply. The labor-intensive process of growing paddy rice requires large numbers of people to work together to level fields, build and maintain bunds, and care for the crop. Where paddy-rice cultivation has been introduced, hard work, organization, persistence, and above all, cooperation, have been encouraged. you can find more here: http://encarta.msn.com/encnet/refpages/RefArticle.aspx?refid=761569224&pn=1&s=14#s14
