The French navy under Admiral de Grasse was sent to the Caribbean in early 1781 with orders to coordinate its activities with General Washington and General Rochambeau on the American mainland. De Grasse, with 20 ships of the line, three frigates and 156 transports, arrived on 22 March 1781 off the coast of Martinique where a British fleet under Admiral Sir Samuel Hood awaited him. Since the French fleet outnumbered the British, Hood did not attack. On 6 May, de Grasse and his fleet sailed into Port Royal. By early June, the French fleet had moved to St. Domingue, modern-day Haiti, with four more ships of the line joining the fleet.
In late Spring of 1781, General Rochambeau informed de Grasse that the allied armies were considering either New York City or the Chesapeake Bay as potential targets for the campaign. Rochambeau hinted that he thought the Chesapeake Bay held greater chances of success but General Washington preferred an attack on New York City, the center of British power on the continent. De Grasse decided to take his fleet to the Chesapeake Bay. The letter informing Washington and Rochambeau of this decision reached the generals in White Plains on 14 August. Admiral de Grasse’s decision had shifted the focus of the war to Virginia. Four days later the allied armies were on their way. The French fleet in Newport under Admiral Barras, with nine ships carrying artillery and supplies for the siege of Yorktown, prepared to sail south to join de Grasse.
In late July, de Grasse, with 28 ships of the line, supporting ships, and carrying nearly 3,300 troops, had headed north. Hood knew that de Grasse would head for the United States and set sail from the West Indies on 10 August. The copper-bottomed British vessels sailed faster than the French, arriving off the Virginia Capes on 25 August. Seeing no French fleet, Hood assumed de Grasse had gone to New York City instead and left to catch up. Finding no French fleet in New York City, Hood joined his vessels to those of Admiral Thomas Graves and headed back to Virginia.
Admiral de Grasse and his fleet arrived at the Virginia Capes on 28 August. In the morning of 5 September, a French lookout saw sails on the horizon, assuming they belonged to Barras’ vessels. However, they represented the British fleet of 19 ships under Admiral Hood and Admiral Graves heading straight for the entrance of the Chesapeake. De Grasse was unprepared, with the wind and tide against him and some of his crews on land. Leaving 90 officers and approximately 1,500 men behind, de Grasse ordered his fleet to sea to do battle with the Royal Navy.
The British ordered a “line ahead” formation, meaning the vessels would sail parallel to the French fleet. In the time it took the British to maneuver, the French were able to sail out of the bay into open waters. As the British waited for the French fleet to approach they provided de Grasse an unexpected, and unintended, opportunity to take advantage of its numerical superiority. The larger French fleet lined up with its best ships parallel to the weakest British ships. The battle began six hours after the first sails were spotted.
Miscommunication resulted in confusion in the British chain of command, with Graves and Hood each signaling different commands. After a battle lasting fewer than three hours later, the Royal Navy disengaged. The British had suffered 336 casualties, the French 240. Five British ships and four French ships were heavily damaged.
The following day, both fleets drifted to the southward while making repairs. Admiral Hood wanted to return to the entrance of the bay but Admiral Graves refused. On 9 September, de Grasse headed back to the entrance of the Chesapeake Bay and found Barras’ fleet anchored within. By drawing the Royal Navy away from the Chesapeake, de Grasse had allowed Barras to bring his fleet safely into the bay. Now Cornwallis was trapped. When Graves returned to the Chesapeake Bay on 13 September his fleet was vastly outnumbered and he chose not to attack.
On 18 September, Generals Washington and Rochambeau visited de Grasse on his flagship, the “Ville de Paris.” The circle around Cornwallis was closed and the siege of Yorktown was about to begin, thanks in part to the victory of the French fleet in the Battle off the Capes.