1777 in the United States

January 3: Battle of Princeton

• January 2 – American Revolutionary War: Battle of the Assunpink Creek, also known as the Second Battle of Trenton: American forces under the command of George Washington repulse a British attack near Trenton, New Jersey.
• January 3 – American Revolutionary War: Battle of Princeton: American general George Washington defeats British general Charles Cornwallis.
• January 12 – Mission Santa Clara de Asís founded in what is now Santa Clara, California.
• January 15 – Vermont declares its independence from New York, becoming the Vermont Republic, an independent country, a status it retains until it joins the United States as the 14th state in 1791.
• January 20 – American Revolutionary War: Battle of Millstone, part of the Forage War
• February 1 – American Revolutionary War: Battle of Drake's Farm, part of the Forage War
• February 8 – American Revolutionary War: Battle of Quibbletown, part of the Forage War
• February 23 – American Revolutionary War: Battle of Spanktown, part of the Forage War

June 14: The Stars and Stripes is adopted by the Continental Congress as the flag of the United States.

• April 13 – American Revolutionary War: Battle of Bound Brook: A British and Hessian force led by Lieutenant General Charles Cornwallis surprises a Continental Army outpost in New Jersey commanded by Major General Benjamin Lincoln.
• April 26 – American Revolutionary War: 16-year-old Sybil Ludington rides 40 miles (64 km) through the night to warn militiamen under the control of her father Henry that British troops are planning to invade Danbury, Connecticut.
• April 27 – American Revolutionary War: The Battle of Ridgefield: A British invasion force engages and defeats Continental Army regulars and militia irregulars at Ridgefield, Connecticut.
• May 16 – Lachlan McIntosh and Button Gwinnett shoot each other during a duel near Savannah, Georgia. Gwinnett, a signer of the United States Declaration of Independence, dies three days later.
• May 17 – American Revolutionary War: Battle of Thomas Creek.
• May 23 – American Revolutionary War: Meigs Raid.
• June 13 – American Revolution: The Marquis de Lafayette lands near Charleston, South Carolina to help the Continental Congress train its army.
• June 14 – The Stars and Stripes is adopted by the Continental Congress as the flag of the United States.
• June 26 – American Revolutionary War: Battle of Short Hills.

August 6: Battle of Oriskany

September 21: Battle of Paoli

• July 6 – American Revolutionary War: Siege of Fort Ticonderoga – After a bombardment by British artillery under General John Burgoyne, American forces retreat from Fort Ticonderoga, New York.
• July 7 – American Revolutionary War: Battle of Hubbardton – British forces engage American troops retreating from Fort Ticonderoga.
• July 8
  • The Constitution of Vermont is adopted. This constitution was the first in what is now the territory of the United States to prohibit slavery, grant suffrage to non-landowning males, and require free public education.
  • American Revolutionary War: Battle of Fort Anne.
• July 31 – The U.S. Second Continental Congress passes a resolution that the services of Marquis de Lafayette "be accepted, and that, in consideration of his zeal, illustrious family and connexions, he have the rank and commission of major-general of the United States."
• August 2–23 – American Revolutionary War: Siege of Fort Stanwix.
• August 6 – American Revolutionary War: Battle of Oriskany – Loyalists gain a tactical victory over Patriots; Iroquois fight on both sides.
• August 13–14 – American Revolutionary War: Battle of Machias.
• August 16 – American Revolutionary War: Battle of Bennington – British forces are defeated by American troops at Walloomsac, New York.
• August 22 – American Revolutionary War: Battle of Staten Island.
• September – American Revolutionary War: Siege of Fort Henry.
• September 3 – American Revolutionary War: Battle of Cooch's Bridge – In a minor skirmish in New Castle County, Delaware, the flag of the United States was flown in battle for the first time.
• September 11 – American Revolutionary War – Battle of Brandywine: The British gain a major victory in Chester County, Pennsylvania.
• September 16 – American Revolutionary War: Battle of the Clouds.
• September 19 – American Revolutionary War: First Battle of Saratoga: Battle of Freeman's Farm – Patriot forces withstand a British attack at Saratoga, New York.
• September 21 – American Revolutionary War: Battle of Paoli.
• September 26 – American Revolutionary War: British troops occupy Philadelphia.
• September 27 – Lancaster, Pennsylvania is the capital of the United States for one day.

October 17: Gen. Burgoyne surrenders to the Americans following the Second Battle of Saratoga

• October 4 – American Revolution – Battle of Germantown: Troops under George Washington are repelled by British troops under Sir William Howe.
• October 5-November 25 – American Revolutionary War: Battle of Red Bank.
• October 6 – American Revolutionary War: Battle of Forts Clinton and Montgomery: British troops capture Fort Clinton and Fort Montgomery (Hudson River) and are able to dismantle the Hudson River Chain.
• October 7 – American Revolution – Second Battle of Saratoga: Battle of Bemis Heights: British General John Burgoyne is defeated by American troops.
• October 17 – American Revolution – Battle of Saratoga: British General John Burgoyne surrenders to the American troops.
• November 15 – American Revolution: After 16 months of debate, the Continental Congress approves the Articles of Confederation in the temporary American capital at York, Pennsylvania.
• November 17 – The Articles of Confederation are submitted to the states for ratification.
• November 25 – American Revolutionary War: Battle of Gloucester
• November 29 – San Jose, California is founded. It is the first pueblo in Spanish Alta California.
• December 5–8 – American Revolutionary War: Battle of White Marsh
• December 11 – American Revolutionary War: Battle of Matson's Ford
• December 18 – The United States celebrates its first Thanksgiving as a nation, marking the victory by the Americans over General John Burgoyne in the Battle of Saratoga in October.
• December 19 – American Revolution: George Washington's Continental Army goes into winter quarters at Valley Forge, Pennsylvania.

In the St. Louis region, a brood of 13-year cicadas emerges at the same time as a large brood of 17-year cicadas.[1]

• American Revolutionary War (1775–1783)
• Slavery in the United States