Battle Description

The Penobscot Expedition was launched by Massachusetts to dislodge a British force that had established Fort George at Castine, aiming to create a new Loyalist colony called “New Ireland.” On July 24, 1779, a combined American force of over 40 ships and 1,000 troops began a siege of the fort. Artillery units under Paul Revere supported the land assault.

However, poor coordination between land and naval commanders—particularly Commodore Dudley Saltonstall’s refusal to engage British ships—stalled the siege. On August 14, a British relief fleet under Commodore George Collier arrived, trapping the American fleet. In a chaotic retreat, the Americans scuttled or burned their ships and fled overland through the Maine wilderness.

Outcome

• Outcome: British victory; American fleet destroyed.
• Casualties:
  • American: ~474 killed, wounded, or captured; entire fleet lost (19 warships, 25 support vessels)
  • British: ~85 killed, wounded, or captured

Significance on the Revolution

The Penobscot Expedition was the worst American naval disaster until Pearl Harbor. It exposed deep flaws in colonial command structure and inter-service rivalry. Massachusetts was left financially crippled, and Commodore Saltonstall was court-martialed and dismissed. The British retained control of eastern Maine for the remainder of the war, and the failed expedition highlighted the need for stronger centralized military coordination.