Volume 6 documents Washington's decisions and actions during the heart of the New York campaign--the period from late summer to early fall 1776 when his British opponent, General William Howe, took the offensive and outmaneuvered the American forces in and around New York City through a series of amphibious landings. Faced with an enemy superior in numbers, mobility, and discipline, Washington attempted to defend New York by placing his green troops behind fortifications on high ground and hoping that courage and patriotism would offset their lack of experience and training. That strategy failed at the Battle of Long Island on 27 August when Howe's army outflanked and routed a larger American force on the Heights of Guana. Two nights later Washington reunited his dangerously divided army by skillfully evacuating every man and most stores and equipment from Long Island to New York City.

During the following weeks Washington spared no one including himself in an effort to restore order and confidence to his badly dispirited troops. He also reassessed his strategy and concluded "that on our side the War should be defensive" and "that we should on all occasions avoid a general Action or put anything to the risque unless compelled by a necessity into which we ought never to be drawn." Reluctantly deciding to abandon New York City, Washington narrowly avoided being forced into a disadvantageous general engagement on 15 September when he marched his army north to defensive positions on Harlem Heights ahead of British and Hessian soldiers landing at Kip's Bay. Although the Battle of Harlem Heights on the following day was an indecisive skirmish between detachments, it raised American morale by showing that some of their troops could and would fight well against enemy regulars in limited actions.

Military concerns so preoccupied Washington that at times his secretary Robert Hanson Harrison had to write the president of Congress and other public officials for him. This volume, nevertheless, includes four long letters that Washington wrote to his plantation manager Lund Washington describing his situation in New York and giving detailed instructions regarding such matters as the sale of flour from the Mount Vernon mill, the remodeling of the mansion house, and the planting of trees around it.