Grapes are one of the earliest cultivated fruits, and probably originated around the Black Sea region. It is estimated that grapes were cultivated in Mesopotamia (Modern day Iraq) as far back as 6,000 B.C. Their cultivation spread to Phoenicia and Egypt and by 2,000 B.C. all over the Mediterranean region.
The whole point of growing grapes in those early days was making wine. The Greeks had Dionysus, who later was renamed Bacchus by the Romans, a god dedicated full time to matters of grapes and wine.
The Romans, in fact, were the first to improve grape cultivation and processing techniques. They realized that climate, soil, pruning and cleanliness could affect the quality of the final product dramatically. But with the decline of the Roman Empire, grape cultivation and wine making declined too. During Medieval times only the Church kept it up, particularly the Benedictine and Cistercian monks in France and Germany. But eventually more grape varieties were grown specially for eating and drying, apart from those destined to wine making.
Immediately following Columbus' first voyages grape culture was transported from Europe to the New World. California in particular owes its original stock to the Spanish Missions. Grape cultivation spread north with the influx of European immigrants and frustrated gold prospectors. More recently, grape cultivation has been taken up in Oregon, Washington State and even in the North East.