Editing Fort Mifflin (section)

== The 1777 Siege ==

When British General William Howe captured Philadelphia in September 1777, he faced a critical problem: his army occupied the city, but the Delaware River defenses prevented British ships from bringing supplies and reinforcements upriver. Howe's army, dependent on supplies shipped from New York, could not sustain itself indefinitely without opening the river. The American forts and obstructions had to be reduced before British control of Philadelphia could be consolidated. Fort Mifflin, protecting the Pennsylvania side of the river, became the focus of an intense siege that would last over five weeks.<ref name="lengel">{{cite book |last=Lengel |first=Edward G. |title=General George Washington: A Military Life |year=2005 |publisher=Random House |location=New York}}</ref>

The British assault on Fort Mifflin combined naval bombardment with land-based artillery positioned on Province Island, just south of the fort. The defenders, numbering only a few hundred men under the command of Lieutenant Colonel Samuel Smith and later Major Simeon Thayer, faced overwhelming firepower. British warships, including ships of the line mounting 64 guns, bombarded the fort from the river while land batteries fired from close range. The wooden palisades and earthen walls provided inadequate protection against this concentrated bombardment. During the siege's final days, the British fired an estimated 10,000 cannonballs at the small fort, reducing much of it to rubble and inflicting severe casualties on the defenders.<ref name="mcguire"/>

The garrison's resistance was remarkable. Soldiers worked through the night to repair damage from each day's bombardment, rebuilding walls and remounting cannon under continuous fire. The wounded were evacuated across the river to Fort Mercer, while fresh troops were brought in to replace casualties. The garrison held out until November 15, 1777, when the surviving defenders—fewer than 200 able-bodied men—evacuated the ruins under cover of darkness, setting fire to what remained. The British had captured the fort, but the five-week delay had allowed Continental forces to secure supplies and establish the defensive position at [[Valley Forge]]. Fort Mercer fell a week later, and the Delaware was finally open to British shipping.<ref name="jackson"/>