The Battle of White Marsh or Battle of Edge Hill was a battle of the Philadelphia campaign of the American Revolutionary War fought December 5–8, 1777, in the area surrounding Whitemarsh Township, Pennsylvania. The battle, which took the form of a series of skirmish actions, was the last major engagement of 1777 between British and American forces. Washington's intelligence network, led by Major John Clark, became aware of British plans to surprise the Americans, through a Quaker housewife named Lydia Darragh. The Continental Army was ready when Howe marched out of Philadelphia, with a force of approximately 14,000 men, at midnight on December 4. It is the first week of December. The Continental Army, encamped for the last month at Whitemarsh, 13 miles northwest of Philadelphia, is waiting for an attack that Washington's spies have assured him is coming. Dug into heavily wooded hills, the Continental troops are in an ugly mood. They are cold, hungry, and tired. And they haven't been paid since late summer. They occupy fortified high ground, a circumstance that fosters feelings of invulnerability. The night sky has convinced some American soldiers that a big battle is coming. Just after midnight on December 5, Cornwallis' vanguard, which consisted of two British light infantry battalions, skirmished with an American cavalry patrol under the command of Capt. Expecting a confrontation, Washington took the precaution of striking his tents before sunrise, and sent the heavy baggage north to Trappe.

The two armies spent December 6 watching each other across the Wissahickon Valley. Howe hoped that Washington would leave his positions to attack the British; Washington did not, preferring instead to let the British do the maneuvering. By day's end, Howe decided upon a flanking movement toward the Americans' left, toward Jenkintown and Cheltenham Township, while Maj. Gen. Charles Grey's forces would create a distraction by attacking the American center. Sometime after 1:00 am on December 7, Howe marched the British Army back through Germantown, and then to Jenkintown, where they remained until noon. As the British movements were concealed by a ridge on Chestnut Hill, just south of the American defenses, and waited for daybreak. On the morning of December 8, British generals and engineers once again studied the American positions, looking for any advantage they could exploit in the American defenses.Washington, frustrated at not being able to confront Howe in a more decisive action, wrote in his report to Henry Laurens, president of Congress, "I sincerely wish, that they had made an Attack; the Issue in all probability, from the disposition of our Troops and the strong situation of our Camp, would have been fortunate and happy.