An 8th-grade U.S. history lesson analyzing the Siege of Yorktown, French-American alliance, and the 1783 Treaty of Paris through Indiana historical causation standards. Students evaluate turning points and long-term consequences that established American independence.
• British forces were entirely trapped on the Yorktown waterfront.
"Without the French Navy, there is no victory at Yorktown."
Turning Point: Control of the sea decided the war on land. Indiana Standard 8.1.11
Act IV • The Climax
Siege Trenches & The Night Assault
Relentless Siege Warfare
Allied forces dug concentric parallel trenches closer and closer to British lines under continuous artillery fire.
By mid-October, Allied cannon fired over 1,700 shells daily, pulverizing Cornwallis's defenses and sinking ships in the harbor.
Cornwallis's troops suffered from disease, starvation, and depleted ammunition.
Storming Redoubts 9 & 10
October 14, 1781: Two advanced British earthen forts blocked Allied completion of the second siege parallel.
French troops stormed Redoubt #9 while Alexander Hamilton led an American bayonet assault with unloaded muskets on Redoubt #10.
Both redoubts were captured in under 30 minutes, sealing the British defeat.
October 17, 1781: A British drummer boy mounted the parapet to beat a "parley" (request for surrender). Total Encirclement
Act V • The Surrender
"The World Turned Upside Down"
October 19, 1781
Nearly 8,000 British and Hessian soldiers marched between French and American ranks to lay down their arms.
Claiming illness, General Cornwallis refused to attend, sending his second-in-command, General Charles O'Hara.
Washington directed O'Hara to surrender his sword to American General Benjamin Lincoln.
Political Reaction in London
When British Prime Minister Lord North received news of Yorktown, he threw his hands in the air and cried:
"Oh God! It is all over!"
The British public and Parliament lost all appetite to fund the expensive transatlantic conflict.
March 1782: Parliament voted to cease offensive operations in America.
Historical Causation: Military defeat directly forced diplomatic surrender. Turning Point Achieved
Act VI • The Consequences
The Treaty of Paris (1783)
Full Independence
Great Britain officially recognized the United States as a free, sovereign, and independent nation.
Expansive Borders
U.S. boundaries extended north to Canada, south to Spanish Florida, and west all the way to the Mississippi River.
Unresolved Tensions
British agreed to withdraw frontier forts; Native Americans were excluded from treaty talks; debts and Loyalist property lingered.
Negotiators: Benjamin Franklin, John Adams, and John Jay secured stunning diplomatic terms.
Indiana Standard 8.1.12
4. Political Reaction: Why did Lord North react so dramatically? How did the military defeat at Yorktown cause a political crisis inside the British Parliament?
Part 4: Terms and Consequences of the 1783 Treaty
Diplomatic Terms
Key Treaty Provision
Significance for the U.S.
Potential Conflict / Limitation
1. Sovereignty Recognized
Britain recognizes U.S. as independent nation.
Must establish stable federal government.
2. New Western Boundary
Territory expands west to Mississippi River.
Ignores Native American land claims.
3. Withdrawal of Troops
British promised to leave forts on U.S. soil.
British delayed withdrawal in Great Lakes.
5. Territorial Growth: How did securing the Mississippi River as the western boundary transform the future of the new United States? (Think about trade, farming, and expansion).
Part 5: Historical Causation Synthesis
Short Essay Response
6. Evaluate: Historians debate whether the American victory at Yorktown was primarily caused by George Washington's military leadership or the intervention of French naval and ground forces. Choose one position or argue that both were equally indispensable, supporting your claim with at least two specific facts from the lesson.
Yorktown Siege & End of the Revolution • Grade 8 Social Studies Page 2 of 2
4. Political Reaction & Crisis in Parliament: 2 Pts
Model Response: Lord North understood that the surrender of a second entire British field army (after Saratoga) broke the will of the British government. The financial cost of waging a global war against America, France, Spain, and the Dutch had become unbearable. In March 1782, Parliament voted to end offensive military operations, and Lord North resigned, leading to a new pro-peace ministry.
5. Significance of the Mississippi River Boundary: 2 Pts
Model Response: Securing the Mississippi River doubled the geographic size of the new nation and removed British restrictions (such as the Proclamation Line of 1763). It opened the fertile Ohio River Valley for American settlement, gave farmers access to vital river trade routes, and laid the foundation for westward expansion, while setting the stage for future conflicts with Native American tribes living on those lands.
Cites deceptive strategy holding Clinton in NYC, disciplined 400-mile coordination, and leadership in parallel siege trench construction.
Strong French Claim / Balanced:
Cites de Grasse's naval victory blocking escape, French heavy artillery, and Rochambeau's veteran siege engineers. Most scholars conclude both were essential.
Treaty Crossroads Exit Ticket Answer Key
Quick-Scan Key (5 Pts Total)
Question 1: B
French fleet victory under de Grasse at Chesapeake Bay.
Question 2: C
Mississippi River established as the western boundary.
Question 3 (2 Pts): Causal Link
Surrender destroyed military capability + public/Parliamentary support collapsed → peace talks initiated.
Yorktown Siege Answer Key • Grade 8 Social Studies Page 2 of 2
