On September 11, 1777, General Howe outflanked Washington along Brandywine Creek in the longest single-day battle of the war. The defeat left the Continental Army unable to stop the British advance.
Days later the British occupied Philadelphia, the rebel capital, sending Congress fleeing. The hard winter that followed at nearby Valley Forge would test whether the army could survive at all.
| Date | September 11, 1777 |
| Outcome | British victory |
| Significance | Opened the road to Philadelphia |
| Date | September 11, 1777 |
| Location | Chadds Ford, Pennsylvania |