In short
In 1788, the United States adopted a new constitution to replace the Articles of Confederation, which had proven too weak to hold the young nation together. After ratification by nine of thirteen states, the document took effect on March 4, 1789, establishing the federal government structure—executive, legislative, and judicial branches—that still governs the country today. The Constitution created a system designed to balance power and protect individual liberties, though it took a civil war and centuries of amendments to live up to that promise.
How it unfolded.
The five-minute version
What actually happened.
The Constitution of the United States is the supreme law of the United States of America. It superseded the Articles of Confederation, the nation's first constitution, on March 4, 1789. Originally including seven articles, the Constitution defined the foundational structure of the federal government.
As it was happening
15 voices, 1665 days.
One beat at a time. Click any dot on the timeline to jump, press play for autoplay, or use the arrow keys to step.
Constitutional Convention opens
Delegates from twelve states convene in Philadelphia to revise the Articles of Confederation. George Washington presides.
Voices from this moment (1)
Constitutional Convention opens
May 25
“Delegates from twelve states convene in Philadelphia to…”
As it was happening
15 voices, 1665 days.
Day 0 · May 25, 1787
Constitutional Convention opens
Delegates from twelve states convene in Philadelphia to revise the Articles of Confederation. George Washington presides.
“Delegates from twelve states convene in Philadelphia to…”
- Constitutional Convention opens, May 25
Day 115 · September 17, 1787
Constitution signed
Thirty-nine delegates sign the final document after four months of debate and compromise.
“Thirty-nine delegates sign the final document after four…”
- Constitution signed, Sep 17
Day 196 · December 7, 1787
Delaware ratifies first
Delaware becomes the first state to ratify, setting the ratification process in motion across the union.
“Delaware becomes the first state to ratify, setting the…”
- Delaware ratifies first, Dec 7
Day 222 · January 2, 1788
Georgia ratifies
Georgia becomes the third state to ratify the Constitution.
“I smell a rat.”
- Virginia Ratifying Convention speech, June 1788, Jun 5
“Georgia becomes the third state to ratify the Constitution.”
- Georgia ratifies, Jan 2
Day 393 · June 21, 1788
Ratification reaches threshold
New Hampshire votes to ratify, becoming the ninth state and meeting the requirement for the Constitution to take effect.
“This Constitution is a colossal monument to human wisdom -…”
- Synthesized from period accounts - The Federalist Papers and speeches, 1787-1788, Jun 21
“When you assemble a number of men to have the advantage of…”
- Synthesized from period accounts - Convention remarks and letters, September 1787, Jun 21
“New Hampshire votes to ratify, becoming the ninth state and…”
- Ratification reaches threshold, Jun 21
Day 398 · June 26, 1788
Virginia ratifies
Virginia's ratification, following a close debate led by James Madison and Patrick Henry, provides crucial endorsement.
“If the Constitution be a good one, is it not to be hoped…”
- Letter to Thomas Jefferson, June 28, 1788, Jun 28
“Virginia's ratification, following a close debate led by…”
- Virginia ratifies, Jun 26
Day 428 · July 26, 1788
New York ratifies
New York ratifies after Alexander Hamilton's Federalist Papers campaign, securing the largest northern state.
“The fabric of American empire ought to rest on the solid…”
- Synthesized from period accounts - Warren correspondence and observations, 1788, Oct 15
“New York ratifies after Alexander Hamilton's Federalist…”
- New York ratifies, Jul 26
Day 649 · March 4, 1789
Constitution takes effect
The Constitution becomes the supreme law of the United States, replacing the Articles of Confederation.
“The Constitution becomes the supreme law of the United…”
- Constitution takes effect, Mar 4
Day 706 · April 30, 1789
George Washington inaugurated
Washington is sworn in as the first President under the new Constitution.
“Washington is sworn in as the first President under the new…”
- George Washington inaugurated, Apr 30
Day 1665 · December 15, 1791
Bill of Rights ratified
The first ten amendments are ratified, addressing concerns from ratification debates about protecting individual liberties.
“The first ten amendments are ratified, addressing concerns…”
- Bill of Rights ratified, Dec 15
The numbers.
3 numbers that anchor the scale.
By the numbers
The countable parts.
Original number of articles
0
States that ratified
0 of 13
Signatories at Convention
0 of 55 delegates
Captured in time.
Captured before it changed
The web as it looked, the day it happened.
Wayback Machine snapshots of the pages people actually loaded that day. Click any card to open the archive at full size.
Sources & citations.
Sources
Where this came from.
Every claim on this page traces to a public, license-clean source. We don't asterisk well.
Wikipedia
1 source- 1.American constitution
en.wikipedia.org