although a stand by 400 Maryland troops prevented a larger portion of the army from being lost
The Old Stone House was the culminating site of what was the largest battle of the Revolutionary War.
On the morning of August 27th, 1776, the British were advancing toward the main American camp on Brooklyn Heights. Realizing the dire American position, the American General, William Alexander, Lord Stirling, led a regiment of 400 Maryland soldiers against 2,000 British forces commanded by General Charles Cornwallis at the Old Stone House. The Marylanders fell, regrouped, and attacked again, but eventually their losses became too great to continue and Stirling finally surrendered. Cornwallis later said that General Lord Stirling “fought like a wolf.”
On August 30, 1776, Maryland Major Mordecai Gist wrote, “The principal loss sustained in our battalion fell on Captains Veazey, Adams, Lucas, Ford, and Bowie’s companies. The killed, wounded, and missing amount to two hundred and fifty-nine.” Where those killed are buried is uncertain to this day.
The outcome of the Battle of Brooklyn was a victory for the British, who killed or captured 1,000 Americans and proceeded to occupy Brooklyn and Manhattan for seven years.
However, the British failed to capture Washington and his army, which withdrew across the East River to fight again and, eventually, win the war.
In 1783, the British finally surrendered, sailing from New York in defeat, and America embarked on its destiny as an independent nation.
http://theoldstonehouse.org/history/battle-of-brooklyn/
At 09:00, Washington arrived from Manhattan.[67] Washington realized that he had been wrong about a feint on Long Island and he ordered more troops to Brooklyn from Manhattan.[67] Washington’s location on the battlefield is not known, because accounts differ, but most likely he was at Brooklyn Heights, where he could view the battle.[68]
On the American right, to the west, Stirling still held the line against Grant.[68] Stirling held on for four hours, still unaware of the British flanking maneuver, and some of his own troops thought they were winning the day because the British had been unable to take their position. However, by 11:00, Grant, reinforced by 2,000 marines, hit Stirling’s center and Stirling was attacked on his left by the Hessians.[65][68] Stirling pulled back but British troops were, at this point, coming at him in his rear south down the Gowanus Road. The only escape route left was across a Brouwer’s millpond on the Gowanus Creek which was 80 yards wide, on the other side of Brooklyn Heights.[69]
Maryland 400
Stirling ordered all of his troops, except a contingent of Maryland troops under the command of Gist, to cross the creek. This group of Maryland troops became known to history as the “Maryland 400”, although they numbered about 260–270 men. Stirling and Gist led the troops in a rear-guard action against the overwhelming numbers of British troops which surpassed 2,000 supported by two cannons.[69]
Stirling and Gist led the Marylanders in two attacks against the British who were in fixed positions in and in front of the Vechte-Cortelyou House (known today as the Old Stone House). After the last assault, the remaining troops retreated across the Gowanus Creek. Some of the men who tried to cross the marsh were bogged down in the mud and under musket fire and others who could not swim were captured.
Stirling was surrounded and, unwilling to surrender, broke through the British lines to von Heister’s Hessians and surrendered to them. Two hundred fifty six Maryland troops were killed in the assaults in front of the Old Stone House, and fewer than a dozen made it back to the American lines.[70] Washington, watching from a redoubt on nearby Cobble Hill (intersection of today’s Court Street and Atlantic Avenue), reportedly said, “Good God, what brave fellows I must this day lose.”[69][note 1]
https://en.wikipedia.org/wiki/Battle_of_Long_Island#Vechte-Cortelyou_House