Washington's army of 11,000 went into winter quarters at Valley Forge north of Philadelphia in December 1777. They suffered between 2,000 and 3,000 deaths in the extreme cold over six months, mostly from disease and lack of food, clothing, and shelter. Meanwhile, the British were comfortably quartered in Philadelphia, paying for supplies in pounds sterling, while Washington struggled with a devalued American paper currency. The woodlands were soon exhausted of game, and by February, lowered morale and increased desertions ensued.

Washington made repeated petitions to the Continental Congress for provisions. He received a congressional delegation to check the Army's conditions and expressed the urgency of the situation, proclaiming: "Something must be done. Important alterations must be made." He recommended that Congress expedite supplies, and Congress agreed to strengthen and fund the army's supply lines by reorganizing the commissary department. By late February, supplies began arriving.

Baron Friedrich Wilhelm von Steuben's incessant drilling soon transformed Washington's recruits into a disciplined fighting force, and the revitalized army emerged from Valley Forge early the following year. Washington promoted Von Steuben to Major General and made him chief of staff.