The Battle of Long Island is also known as the Battle of Brooklyn and the Battle of Brooklyn Heights. It was fought on August 27,1776 and was the first major battle of the American Revolutionary War to take place after the United States declared its independence on July 4,1776. It was a victory for the British Army and the beginning of a campaign that gave them control of the strategically important city of New York. In terms of troop deployment and fighting, it was the largest battle of the entire war, Washington understood that the citys harbor would provide an excellent base for the British Navy during the campaign, so he established defenses there and waited for the British to attack. After five days of waiting, the British attacked American defenses on the Guan Heights, unknown to the Americans, however, Howe had brought his main army around their rear and attacked their flank soon after. The Americans panicked, resulting in twenty percent losses through casualties and captures, the remainder of the army retreated to the main defenses on Brooklyn Heights. The British dug in for a siege but, on the night of August 29–30, Washington and the Continental Army were driven out of New York entirely after several more defeats and forced to retreat through New Jersey and into Pennsylvania. In the first stage of the war, the British Army was trapped in the city of Boston and they abandoned it on March 17, setting sail to Halifax. Washington then began to transfer regiments to New York City which he believed the British would next attack because of its strategic importance. Washington left Boston on April 4, arrived at New York on April 13, Washington had sent his second in command Charles Lee ahead to New York the previous February to establish the citys defenses. Lee remained in New York City until March, when the Continental Congress sent him to South Carolina, troops were in limited supply, so Washington found the defenses incomplete, but Lee had concluded that it would be impossible to hold the city with the British commanding the sea. He reasoned that the defenses should be located with the ability to inflict casualties upon the British if any move was made to take. Barricades and redoubts were established in and around the city, Lee also saw that the immediate area was cleared of Loyalists. Washington began moving troops to Brooklyn in early May, and there were several thousand of them there in a short time. Three more forts were under construction on the side of the East River to support Fort Stirling. These new fortifications were Fort Putnam, Fort Greene, and Fort Box and they lay from north to south, with Fort Putnam farthest to the north, Greene slightly to the southwest, and Box slightly farther southwest. Each of these structures was surrounded by a large ditch, all connected by a line of entrenchments. Fort Defiance was also being constructed at this time, located farther southwest, past Fort Box, hulks were sunk at strategic locations to deter the British from entering the East River and other waterways
The Delaware Regiment at the Battle of Long Island
American strategy called for the first line of defense to be based on the Heights of Guan, a series of hills which stretched northeast across King's County. The main defensive works were a series of forts and entrenchments located in the northwest of the county, in and around the Dutch-founded town of Brookland. The "Road to Narrows" is the Gowanus Road. No. 5 is the "Old Stone House". Map by Bernard Ratzer based on his 1766-1767 survey.
The British fleet in the lower bay (Harpers Magazine, 1876) depicts the British fleet amassing off the shores of Staten Island in the summer of 1776
British troops in the type of flat-bottomed boat used for the invasion of Long Island. Hessians in their blue uniforms are in the two boats that are only partly visible.