sail until 19 October, two days after Cornwallis surrendered. Background During the early months of 1781, both pro-British and rebel separatist forces began concentrating in Virginia, a state that had previously not had action other than naval raids. The British forces were led at first by the turncoat Benedict Arnold, and then by William Phillips before General Charles, Earl Cornwallis, arrived in late May with his southern army to take command. In June, Cornwallis marched to Williamsburg, where he received a confusing series of orders from General Sir Henry Clinton that culminated in a directive to establish a fortified deep-water port (which would allow resupply by sea). In response to these orders, Cornwallis moved to Yorktown in late July, where his army began building fortifications. The presence of these British troops, coupled with General Clinton's desire for a port there, made control of the Chesapeake Bay an essential naval objective for both sides. On 21 May, Generals George Washington and Rochambeau, respectively the commanders of the Continental Army and the Expédition Particulière, met at the Vernon House in Newport, Rhode Island to discuss potential operations against the British and Loyalists. They considered either an assault or siege on the principal British base at New York City, or operations against the British forces in Virginia. Since either of these options would require the assistance of the French fleet, then in the West Indies, a ship was dispatched to meet with French Lieutenant général de Grasse who was expected at Cap-Français (now known as Cap-Haïtien, Haiti), outlining the possibilities and requesting his assistance. Rochambeau, in a private note to de Grasse, indicated that his preference was for an operation against Virginia. The two generals then moved their forces to White Plains, New York, to study New York's defenses and await news from de Grasse. Arrival of the fleets De Grasse arrived at Cap-Français on 15 August. He immediately dispatched his response to Rochambeau's note, which was that he would make for the Chesapeake. Taking on 3,200 troops, De Grasse sailed from Cap-Français with his entire fleet, 28 ships of the line. Sailing outside the normal shipping lanes to avoid notice, he arrived at the mouth of the Chesapeake Bay on August 30, and disembarked the troops to assist in the land blockade of Cornwallis. Two British frigates that were supposed to be on patrol outside the bay were trapped inside the bay