As the Franco-American force marched through New Jersey into Maryland, de Grasse’s fleet arrived on the Chesapeake on 31 August 1781. The French ships placed a blockade across the entrance of the bay while the Continental Army of the Southern Department led by Maj. Gen. Nathanael Greene and including General Lafayette and General von Steuben kept an eye on General Clinton and his army that were now occupying Yorktown. Facing enemies by sea and by land, Cornwallis continued to build his defenses as he awaited the arrival of a British relief fleet from New York City.
"Dear COLO,__The long expected fleet from france is at last arrived, they made their appearance in the Chesapeak the 26th ult [August] with 28 ships of the Line and 5000 Land troops which have joined the Marquis [de Lafayette] and we hope effectually prevented Cornwallis's retreat to the Carolinas. He observes this and is fortifying himself with the greatest industry. We shall look as stern as the grave upon him about the 14th his position is at York & Gloster in Virginia on the South and North margin of York River--the fleet on their passage fell in with and captured a Packet from Charles Town bound to Europe on board of which was Lord Rawdon the plunderer of the South, returning to bask in the sunshine of Ministerial favors for butchering the patriotic Sons of America."
Lt. Col. William S. Smith, aide-de-camp, to Col. Samuel B. Webb, Third Connecticut Continental Line, 7 September 1781Henry Phelps Johnston. “The Yorktown Campaign and the Surrender of Cornwallis, 1781.” De Capo Press, 1971, 168.