Rather than spend time building this force into an effective army, Gates decided to march directly to Camden, across a relatively barren area, populated largely by loyalists. The march began on 27 July, only two days after he joined the army. His troops were soon hungry and many of the militia deserted on the march.
Meanwhile, Cornwallis had decided to reinforce the position at Camden, arriving there on 13 August. Despite this reinforcement, Cornwallis was still outnumbered, with 817 British regulars supported by 1,226 loyalists giving him a total of 2,043 against Gates' 3,100. Learning about the American advance, Cornwallis decided to launch his own attack, on after dark on the 15th of August led his troops towards the American force. The two forces met in the dark and prepared for battle.
Gates now made a serious mistake. His Continental Regulars, commanded by Johann De Kalb, were all placed on the right wing, with the militia unsupported on the left against the British regulars. This was soon to be his undoing. While the Continentals more than held their own, even threatening to defeat the British left wing, the militia did not. Thinking that the British facing them were changing formation, the Virginia militia were ordered to attack. However, the British were advancing, not deploying, and exposed to British fire the Virginia militia fired a ragged volley before fleeing. Seeing this, the North Carolina militia fled without even firing.
The commander of the British right wing, Colonel James Webster, now managed an impressive manoeuvre, turning his men left to attack the exposed American regulars from their flank rather than letting them pursue the already defeated militia. De Kalb's position was now hopeless, and by noon the battle was over. De Kalb was mortally wounded, and the army was in flight, led by Gates, who fled 70 miles before resting.
The defeat was made more total as the remnants of the American force were forced to retreat through hostile territory. The Americans lost 800 dead and wounded, while Cornwallis suffered 300 casualties. He also took 1,000 prisoners and captured the American supplies. Only half of the 1,400 Continentals escaped the defeat. In the aftermath, South Carolina was temporarily secured for the British, and North Carolina left vulnerable.