Tobacco was‘s most successful cash crop. The tobacco that the first English settlers encountered in Virginia—the Virginia Indians’ Nicotiana rustica—tasted dark and bitter to the English palate; it was who in 1612 obtained Spanish seeds, or Nicotiana tabacum, from the Orinoco River valley—seeds that, when planted in the relatively rich bottomland of the James River, produced a milder, yet still dark leaf that soon became the European standard. Over the next 160 years, tobacco production spread from the Tidewater area to the Blue Ridge Mountains, especially dominating the agriculture of the Chesapeake region. Beginning in 1619 the General Assembly put in place requirements for the inspection of tobacco and mandated the creation of port towns and warehouses. This system assisted in the development of major settlements at Norfolk, Alexandria, and . Tobacco formed the basis of the colony’s economy: it was used to purchase the and enslaved laborers to cultivate it, to pay local taxes and tithes, and to buy manufactured goods from England. Promissory notes payable in tobacco were even used as currency, with the cost of almost every commodity, from servants to wives, given in pounds of tobacco. Large planters usually shipped their tobacco directly to England, where consignment agents sold it in exchange for a cut of the profits, while smaller planters worked with local agents who bought their tobacco and supplied them with manufactured goods. In the mid-seventeenth century, overproduction and shipping disruptions related to a series of British wars caused the price of tobacco to fluctuate wildly. Prices stabilized again in the 1740s and 1750s, but the financial standings of small and large planters alike deteriorated throughout the 1760s and into the 1770s. By the advent of the American Revolution (1775–1783), some planters had switched to growing food crops, particularly wheat; many more began to farm these crops to support the war effort. In the first year of fighting, tobacco production in Virginia dropped to less than 25 percent of its annual prewar output.