This 1781 pen-and-ink and watercolor manuscript map shows the fortifications and houses of Portsmouth, Virginia, at the time of the American Revolution. Portsmouth served as a primary British post and naval base. On July 4, 1781, British general Charles Cornwallis (1738–1805) left Williamsburg, Virginia, in order to cross the James River and reach Portsmouth. Once at Portsmouth, the British army loaded onto transports. Cornwallis and his men then sailed to Yorktown, where the British defeat at the Siege of Yorktown would conclude the American Revolution. The map shows the military headquarters, fortifications, an artillery park, and powder magazine. Just outside the town is the Habitations de Negres, presumably slave quarters of some kind. The map shows the Portsmouth waterfront along the James and Elizabeth Rivers. Portsmouth was founded in 1752, but dates back even further as a notable shipbuilding site. The map is oriented with north to the right. Relief is shown by shading. Scale is given in toises, an old French unit measuring almost 1.95 meters. The map is from the Rochambeau Collection at the Library of Congress, which consists of 40 manuscript maps, 26 printed maps, and a manuscript atlas that belonged to Jean-Baptiste-Donatien de Vimeur, comte de Rochambeau (1725‒1807), commander in chief of the French expeditionary army (1780‒82) during the American Revolution. Some of the maps were used by Rochambeau during the war. Dating from 1717 to 1795, the maps cover much of eastern North America, from Newfoundland and Labrador in the north to Haiti in the south. The collection includes maps of cities, maps showing Revolutionary War battles and military campaigns, and early state maps from the 1790s.