However, the high number of British casualties in the overall expedition against Groton and New London led to criticism of Arnold by some of his superiors.

The battle was the last major military encounter of the war in the northern United States, preceding and being overshadowed by the decisive Franco-American Siege of Yorktown about six weeks later.

It was originally a part of New London, its larger counterpart on the other side of the Thames River on the northern shore of Long Island Sound.

[7] Both were typically garrisoned by small companies of militia, including a few artillerymen, and overall command of the area's defenses was directed by Lieutenant Colonel William Ledyard.

[10] He only planned it as a raid, but he also believed that New London could be used as a base for further operations into the interior of New England if a permanent British occupation could be established.

The expedition also included about 100 Hessian jägers, a small number of artillerymen, three six-pound guns, and a howitzer, all of which were divided among the divisions.

[8][14] These troops were embarked on transports and sailed on September 4 in the company of a fleet of smaller armed ships, led by Commodore John Bazely in the fifth-rate HMS Amphion.

[16]Upon receiving the alert, Ledyard sent a messenger to notify Governor Jonathan Trumbull and local militia leaders of the British arrival, and went to Fort Griswold to arrange its defenses.

Under the orders given, parts of the town were supposed to be spared, some of which was the property of those secretly loyal to the British, but at least one of the storehouses contained a large quantity of gunpowder, which Arnold evidently had not known.

[20] Meanwhile, Lieutenant Colonel Eyre's force of 800 men landed on the east side of the Thames River, but they were slowed by tangled woodlands and swamplands.

The New Jersey Loyalists landed after the initial wave of regulars, also delayed by the difficulty in moving the artillery through rough conditions, and they did not participate in the assault.

[25] Stephen Hempstead, a sergeant in Shapley's Company, recounted, "When the answer to their demand had been returned... the enemy were soon in motion, and marched with great rapidity, in a solid column... they rushed furiously and simultaneously to the assault of the southwest bastion and the opposite sides.

This unit gained the bastion against fierce resistance, but Montgomery was killed by the thrust of a 10-foot pike from Jordan Freeman, a black man who had previously been a slave[citation needed] in service to Colonel Ledyard.

[29] According to these accounts, the British continued to fire on the Americans despite Ledyard's signs of surrender[clarification needed], and much of the garrison was consequently either killed or seriously wounded.

"[33] Rufus Avery believed that the attack was called off due to the chance that further musket fire might set off the fort's powder magazine.

[37] William Gordon, however, reported in his 1788 history of the war that the "Americans had not more than a half dozen killed" before the fort was stormed, and that "a severe execution took place after resistance ceased."

He wrote, further, that Ledyard “presented him his sword” and was "immediately run through and killed", but doesn’t mention the details which appear in later accounts.

The first person I saw afterwards, was my brave commander, a corpse by my side, having been run through the body with his own sword…" [41] Two black men and one indigenous man are recorded among the defenders of Fort Griswold.

[citation needed] The casualties and losses at Fort Griswold marked one of the greatest in the history of Groton and Connecticut, and was one of the last British victories in North America before the end of the war.

[46] Arnold reported that 85 men "were found dead in Fort Griswold, and sixty wounded, most of them mortally.

[48] Clinton praised Arnold for his "spirited conduct", but also complained about the high casualty rate; about 25 percent of the troops sent against Fort Griswold were killed or wounded.

[49] Arnold next proposed a raiding expedition against Philadelphia, but the surrender of Lieutenant General Charles Cornwallis at Yorktown in late October ended that idea.

Japhet Mason Sailors: According to a plaque at the gate to Fort Griswold, American casualties were as follows:[55] 85 killed, 35 wounded and paroled, 28 taken prisoner, 13 escaped, 1 captured and released (10 year old William Latham Jr.).

Operating on the New London side (west bank of the Thames River) (approximately 900 total soldiers) Brig.

General Benedict Arnold Operating on the Groton side (east bank of the Thames River) (approximately 800 total soldiers) Lt.

Colonel Edmund Eyre (w), Maj. William Montgomery (k), Maj. Stephen Bromfield British casualties were officially reported as 48 killed and 145 wounded.