The West in the late 17th and early 18th centuries referred to western Virginia – the Piedmont Plateau, Blue Ridge Mountains, Shenandoah Valley, and later, areas in Kentucky and Ohio. The earliest colonists took up the valuable tidelands along the river valleys in eastern Virginia. Later immigrants had to seek their opportunities inland. In addition to immigration, the soil-depleting nature of tobacco production also induced westward movement. New lands had to be cleared to keep the tobacco economy profitable. It was difficult for small-scale farmers to compete with slave labor plantations, so many immigrants pushed ever farther westward and eventually clashed with the French in the Ohio Valley. The contested western areas figured prominently in the French and Indian War (1754-1763). The peace treaty at the end of that war prohibited English colonists from crossing the Allegheny Mountains, but that provision was routinely ignored by the settlers. Confrontations with the Native Americans continued and culminated in Lord Dunmore`s War in 1774. This campaign against Shawnee forces ended with the Battle of Point Pleasant (today in West Virginia), a defeat that quelled the native forces in the West.