Success at Savannah led the British to invade South Carolina. Early in 1780, British forces under General Clinton landed near Charleston. They slowly closed in on the city, trapping its defenders. On May 12, General Lincoln surrendered his force of about 5,500 patriots -- almost the entire Southern army. Clinton placed General Charles Cornwallis in charge of British forces in the South and returned to New York City.

The loss of Charleston and so many patriot soldiers badly damaged American morale. However, the British victory had an unexpected result. Soon afterward, bands of South Carolina patriots began to roam the countryside, battling loyalists and attacking British supply lines. The rebels made it risky for loyalists to support Cornwallis. The chief rebel leaders included Francis Marion, Andrew Pickens, and Thomas Sumter.

In July 1780, the Continental Congress ordered General Horatio Gates, the victor at Saratoga, to form a new Southern army to replace the one lost at Charleston. Gates hastily assembled a force made up largely of untrained militiamen. The rest of his men consisted of disciplined Continentals. He rushed to challenge Cornwallis at a British base in Camden, S.C.

On Aug. 16, 1780, the armies of Gates and Cornwallis unexpectedly met outside Camden and soon went into battle. The militiamen quickly panicked and most of them turned and ran without firing a shot. The Continentals fought on until heavy casualties forced them to withdraw. The British had defeated a second American army in the South.

The disaster at Camden marked the low point in the Revolutionary War for the patriots. They then received a further blow. In September 1780, the patriots discovered that General Arnold, who commanded a military post at West Point, N.Y., had joined the British side. The Americans learned of Arnold's treason just in time to stop him from turning West Point over to the enemy.

Cornwallis' victory at Camden in August 1780 led him to act more boldly. In September, he charged into North Carolina before the Loyalists had gained firm control of South Carolina. After Cornwallis' departure, rebels in South Carolina terrorized suspected loyalists. In addition, patriot frontiersmen turned out to fight the British.

In October 1780, the left wing of Cornwallis' army, which was made up of loyalist troops, was surrounded and captured on Kings Mountain, just inside South Carolina. After the defeat at Kings Mountain, Cornwallis temporarily halted his Southern campaign and retreated to South Carolina.

In October 1780, the Continental Congress named Major General Nathanael Greene to replace Gates as commander of the Southern army. Greene was a superb choice because he knew how to accomplish much with extremely few resources. Greene divided his troops into two small armies. He led one army and put Brigadier General Daniel Morgan in charge of the other. Greene hoped to avoid battle with Cornwallis' far stronger force while he rebuilt the Southern army. Instead, Greene planned to let the British chase the Americans around the countryside. The plan worked; Cornwallis set out to trap Morgan's army.