The Pennsylvania Navy served as the naval force of Pennsylvania during the American Revolution and afterward, until the formation of the United States Navy. The navy's vessels served almost exclusively on the Delaware River, and were active in first defending the approaches to the city of Philadelphia during the British campaign that successfully occupied the city in 1777, and then preventing the Royal Navy from resupplying the occupying army.

The Philadelphia campaign (1777–1778) was a British military campaign during the American Revolutionary War designed to gain control of Philadelphia, the Revolutionary-era capital where the Second Continental Congress convened and formed the Continental Army and appointed George Washington as its commander in 1775, and authored and unanimously adopted the Declaration of Independence the following year, on July 4, 1776, which formalized and escalated the war.