In 1751, the English colonist Christopher Gist explored areas along the Ohio River. Following the defeat of France in the French and Indian War (part of the Seven Years' War in Europe), it ceded control of its territory east of the Mississippi River to Britain. In 1769, British colonist Daniel Boone created a trail from North Carolina to Tennessee. He spent the next two years exploring Kentucky. In 1773, Captain Thomas Bullitt led the first exploring party into Jefferson County, surveying land on behalf of Virginians who had been awarded land grants for service in the French and Indian War. In 1774, James Harrod began constructing Fort Harrod in Kentucky. However, battles with the Native American tribes established in the area forced these new settlers to retreat. They returned the following year, as Boone built the Wilderness Road and established Fort Boonesborough at a site near Boonesborough, Kentucky. The Native Americans allocated a tract of land between the Ohio River and the Cumberland River for the Transylvania Land Company. In 1776, the colony of Virginia declared the Transylvania Land Company illegal and created the county of Kentucky in Virginia from the land involved. George Rogers Clark made the first Anglo-American settlement in the vicinity of modern-day Louisville in 1778, during the American Revolutionary War. He was conducting a campaign against the British in areas north of the Ohio River, then called the Illinois Country. Clark organized a group of 150 soldiers, known as the Illinois Regiment, after heavy recruiting in Virginia and Pennsylvania. On May 12, they set out from Redstone, today's Brownsville, Pennsylvania, taking along 80 civilians who hoped to claim fertile farmland and start a new settlement in Kentucky. They arrived at the Falls of the Ohio on May 27. It was a location Clark thought ideal for a communication post. The settlers helped Clark conceal the true reason for his presence in the area. The regiment helped the civilians establish a settlement on what came to be called Corn Island, clearing land, and building cabins and a springhouse. On June 24, Clark took his soldiers and left to begin their military campaign. A year later, at the request of Clark, the settlers crossed the river and established the first permanent settlement on the mainland. By April, they called it "Louisville", in honor of King Louis XVI of France, whose government and soldiers aided colonists in the Revolutionary War. Today, George Rogers Clark is recognized as the European-American founder of Louisville; many landmarks have been named for him. During its earliest history, the colony of Louisville and the surrounding areas suffered from Indian attacks, as Native Americans tried to push out the encroaching colonists.