The Battle of Long Island, also known as the Battle of Brooklyn or the Battle of Brooklyn Heights, fought on August 27, 1776, is the first major battle in the American Revolutionary War following the United States Declaration of Independence, the largest battle of the entire conflict, and the first battle in which an army of the United States engages, having declared itself a nation only the month before.After defeating the British in the Siege of Boston on March 17, 1776, General George Washington, Commander-in-Chief, brings the Continental Army to defend the strategic port city of New York, at this time limited to the southern end of Manhattan Island.

Washington understands that the city's harbor will provide an excellent base for the British Navy during the campaign.

There he establishes defenses and wais for the British to attack.

In July, the British, under the command of General William Howe, land a few miles across the harbor on sparsely populated Staten Island, where over the next month and a half they are slowly reinforced by ships in Lower New York Bay, bringing their total force to 32,000 men.

With the British fleet in control of the entrance to the harbor at The Narrows, Washington knows the difficulty in holding the city.

Believing Manhattan will be the first target, he moves the bulk of his forces there.On August 22, the British land on the southwest shore of Brooklyn, across The Narrows from Staten Island, in what is now the neighborhood of Bay Ridge, more than a dozen miles south from the East River crossings to Manhattan.

After five days of waiting, the British attack American defenses on the Guan Heights.

Unknown to the Americans, however, Howe has brought his main army around their rear and attacks their flank soon after.

The Americans panic, although a stand by 400 Maryland troops prevents most of the army from being captured.

The remainder of the army flees to the main defenses on Brooklyn Heights.

The British dig in for a siege but, on the night of August 29–30, Washington evacuates the entire army to Manhattan without the loss of materiel or a single life.

Washington and the Continental Army are driven out of New York entirely after several more defeats and forced to retreat through New Jersey and into Pennsylvania.