The Philadelphia campaign (1777–1778) is a British initiative in the American Revolutionary War to gain control of Philadelphia, which is at this time the seat of the Second Continental Congress.

British General William Howe, after unsuccessfully attempting to draw the Continental Army under General George Washington into a battle in northern New Jersey, embarks his army on transports, and lands them at the northern end of Chesapeake Bay.

From here, he advances northward toward Philadelphia.

Washington prepares defenses against Howe's movements at Brandywine Creek, but is flanked and beaten back in the Battle of Brandywine on September 11, 1777.

After further skirmishes and maneuvers, Howe is able to enter and occupy Philadelphia.

Washington now unsuccessfully attacks one of Howe's garrisons at Germantown before retreating to Valley Forge for the winter.

Howe's campaign is controversial because, although he successfully captures the American capital of Philadelphia, he proceeds slowly and does not aid the concurrent campaign of John Burgoyne further north, which ends in disaster at Saratoga for the British, and brings France into the war.

General Howe resigns during the occupation of Philadelphia and is replaced by his second-in-command, General Sir Henry Clinton.

Clinton evacuates the troops from Philadelphia back to New York City in 1778 in order to increase that city's defenses against a possible Franco-American attack.

Washington harries the British army all the way across New Jersey, and successfully forces a battle at Monmouth Court House that is one of the largest battles of the war.

At the end of the campaign the two armies are roughly in the same positions they had been at its beginning.