Gen. George Washington, on the Retreat to Valley Forge, Hears the Start of the Final Stand at Forts Mifflin and Mercer, Which Forts Stalled the Enemy and Ensured His Army’s Safe Arrival

He praises the conviction and fearlessness of the men, under the command of Gen. James Varnum, that stalled the British and protected the Delaware River; and extolls preparation for the “Reception of the Enemy at Forts Mercer and Mifflin and that the Garrisons were so full of confidence.”

 

Washington was correct: On November 10, the British had opened a full-scale bombardment of Fort Mifflin, and the heroics of the small detachment there allowed him and the Continental Army to reach Valley Forge

 

The American defense of these forts tied up British resources for seven weeks, preventing them from fully using the Delaware River and supplying Philadelphia. This delay allowed General Washington’s army to move to Valley Forge and prepare for the following year

 

There is no greater symbol of American bravery than the endurance to survive the brutal winter by the Continental Army encamped at Valley Forge in the Winter of 1777-78. But the alternative could have been worse had it not been for heroics on the retreat there.

In September and October of 1777, Washington suffered serious reverses in Pennsylvania at the battles of Brandywine and Germantown; the British then occupied Philadelphia, driving away the Congress. By November, the Americans were encamped around Whitemarsh, 12 miles from Philadelphia. Washington’s inclination was still to attack and retake the city, but he dared not because his forces were in poor condition and a failure might well mean the end of the Continental Army. He said, “Our situation…is distressing from a variety of irremediable causes.” He also considered changing his encampment if he could get away. A move to Valley Forge, 20 miles from Philadelphia, would be advantageous because he could keep an eye on the enemy in Philadelphia in a location that was easily defended, had abundant water, and plenty of wood for fuel and making huts for the winter.

After an exhausting march from Whitemarsh, the American force of 8,000 Continentals and 3,000 militia arrived at Valley Forge on December 19, and they were in a miserable state (just four days later nearly 3,000 men were reported sick or incapable of duty). The winter came on and the men suffered badly from the cold. Except for officers, they slept in six-foot square tents made of canvas, which were weak and cracked and didn’t provide sufficient protection from the snowy weather. Clothing was in very short supply, and many soldiers had to go barefoot or wear only one layer of clothes (at one time 4,000 men were so destitute of clothing that they could not leave their tents). The food, when available, was inadequate. Smallpox and other diseases also ravaged the army at Valley Forge. By mid-winter, 5,000 men had died or left because of illness or the awful conditions. The entire American Army thereafter consisted of some 6,000 men huddled on frozen ground around campfires. British general Howe, by way of contrast, had some 15,000 well-supplied men in and around Philadelphia, and many more available in nearby New York. And yet the American army survived and went on to victory.

In the leadup to that encampment, after the fall of Philadelphia, Forts Mercer and Mifflin played a crucial role in the American war plan by obstructing broader British naval access to Philadelphia to supply the enemy theer. Fort Mercer, built on the New Jersey side of the Delaware River, and Fort Mifflin, located on Mud Island in the river, were designed to block British supply lines and prevent them from re-supplying their occupying forces in the city. The forts were particularly important during the British occupation of Philadelphia, which lasted from September 1777 to June 1778. Fort Mifflin was besieged by British forces from September 26 to November 16, 1777. The siege involved extensive naval bombardment and amphibious assaults. After suffering heavy casualties and running low on ammunition, it was evacuated by the Americans on the night of November 15, 1777. The British took control of Fort Mifflin the next morning. Fort Mercer was built to reinforce Fort Mifflin on the other side of the Delaware River. It was the site of the Battle of Red Bank on October 22, 1777, where American forces successfully repelled a British and Hessian assault. Fort Mercer had to be abandoned after Fort Mifflin fell, and the British occupied it. The American defense of Forts Mercer and Mifflin tied up British resources for nearly seven weeks, preventing them from fully using the Delaware River and supplying Philadelphia. It was the heroic duty of approximately 400 hundred American soldiers stationed at Fort Mifflin to fight the British Navy “to the last extremity” and enable Washington’s safe arrival at Valley Forge. This delay allowed General Washington’s army to move to Valley Forge and prepare for the following year.

James Varnum was an Continental General who had assembled a militia unit when news of the battles of Lexington and Concord reached East Greenwich, Rhode Island, and within a matter of hours the armed men started their march to Boston. In May 1775, the General Assembly commissioned Varnum Colonel of the 1st Regiment of Rhode Island. In 1776 the regiment was incorporated into the Continental Army as the 9th Continental Foot under the command of Brigadier General Nathanael Greene. From 1775 to 1779, Varnum and his men were one of the army’s fighting regiments. They served during the siege of Boston, the Battles of Bunker Hill, Long Island, Monmouth, and others.

In late 1777, Varnum commanded the heroic Continental Army troops at Forts Mercer and Mifflin, for which he received a commendation. In the winter of 1777 at Valley Forge, Varnum, corresponding with his home state and Congress, attempted to procure provisions for his troops. His administrative skills caused Washington to refer to Varnum as “the light of the camp”. In June 1778, Varnum left his troops to return home to Rhode Island for special duties. Varnum suggested to Washington that Rhode Island raise a battalion of negro troops. After General Washington sent the proposal to the governor of Rhode Island, the Rhode Island General Assembly promptly passed legislation authorizing the enlistment of black soldiers and Indians. Later, Varnum would be elected to the Continental Congress in 1780, 1782, and again in 1787, when he supported the new federal Constitution.

Letter signed, Head Quarters at Whitemarsh, Pa., November 10, 1777, to Gen. Varnum, mentioning the forts he had under his command. “Dear Sir, I am pleased to find by yours of the 8th that proper dispositions were formed for the Reception of the Enemy at Forts Mercer and Mifflin and that the Garrisons were so full of confidence. We already hear a firing which we suppose a prelude to something more serious. I sincerely wish you success; but let the event be fortunate or otherwise pray let me have the speediest intelligence. I am Dr Sir Yr most obt. Servt., G. Washington.” He adds a PS telling Varnum that reinforcements are on the way: “Your detachments are on their march from Fishkill to join you.” The body of the letter is in aide Tench Tilghman’s hand, with signature in Washington’s.

Washington was correct: On November 10, the British opened a full-scale bombardment of Fort Mifflin which lasted for five days. Six British warships, with two small floating batteries, HMS Vigilant and HMS Fury, also joined the bombardment to rake Fort Mifflin at close range.

After five days, 250 of the original 400 American defenders had been reported as casualties and ammunition at the fort was running low. The commanding officer of Fort Mifflin, Major Simeon Thayer, ordered the fort abandoned on the evening of November 15. The remaining defenders were evacuated to Fort Mercer, but they left the American flag flying over Fort Mifflin. The next morning, a small party of British troops landed unopposed at the deserted fort, tore down the American flag, and ran up the Union Jack.

The battle at Fort Mifflin has been described as the “greatest bombardment of the American Revolution and one that many say changed the course of American history.” Washington and his troops emerged from their winter encampment at Valley Forge as a much stronger army and eventually won the war.

This is a significant letter in a number of ways. Washington praises his men’s readiness and confidence facing the British at a crucial moment, and warns that “something more serious” may be imminent. He addresses the commander of the key forts Mifflin and Mercer, which had to date kept the British at bay, and wishes him success and asks to be kept informed of developments. We have never had anything like it.