On January 27, 1777, William was promoted to the rank of major and assigned to the newly created 4th Continental Light Dragoons. In the fall of 1778, he was assigned to the 3rd Continental Light Dragoons, which was severely mauled in a surprise attack on the night of September 27 at Old Tappan, New Jersey, by a force of British light infantry. Only 55 of the lightly armed dragoons escaped the attack and their commander, Lt. Col. George Baylor, was wounded and captured. Washington was promoted to lieutenant colonel and placed in command of the 3rd Light Dragoons on November 20, 1778. Washington's unit spent the summer of 1779 recruiting and remounting. On November 19, 1779, his unit was transferred to the Southern theatre of war, and marched to join the army of Major General Benjamin Lincoln in Charleston, South Carolina.