By: HISTORY.com Editors
The Great Northeast Blackout
At dusk on November 9, 1965, one of the biggest power failures in history occurs as all of New York state, portions of seven nearby states, and parts of eastern Canada are plunged into darkness. The Great Northeast Blackout began at the height of rush hour, delaying millions of commuters, trapping 800,000 people in New York’s subways, and stranding thousands more in office buildings, elevators, and trains. Ten thousand National Guardsmen and 5,000 off-duty policemen were called into service.
The blackout was caused by the tripping of a 230-kilovolt transmission line near Ontario, Canada, at 5:16 p.m., which caused several other heavily loaded lines also to fail. This precipitated a surge of power that overwhelmed the transmission lines in western New York, causing a “cascading” tripping of additional lines, resulting in the eventual breakup of the entire Northeastern transmission network. All together, 30 million people in eight U.S. states and the Canadian provinces of Ontario and Quebec were affected by the blackout. During the night, power was gradually restored to the blacked-out areas, and by morning power had been restored throughout the Northeast.
On August 14, 2003 another major blackout occurred which affected most of Eastern Canada as well as most of the Eastern United States.
Photos of the 2003 Blackout: When the Northeast Went Dark
For two days New Yorkers slept on sidewalks, walked home, even showered on the streets and generally made do as the city was crippled without power.
For two days New Yorkers slept on sidewalks, walked home, even showered on the streets and generally made do as the city was crippled without power.
Also on This Day in History
Discover more of the major events, famous births, notable deaths and everything else history-making that happened on November 9th
Related
Natural Disasters & Environment
30 videosArchaeological discoveries have raised questions about whether Mount Vesuvius erupted in the summer or autumn of A.D. 79.
Experts suspect the massive event that flattened forests was caused by an exploding asteroid. Could it happen again?
A powerful El Niño triggered devastating droughts and famines around the world, leaving millions dead.
About the author
HISTORY.com works with a wide range of writers and editors to create accurate and informative content. All articles are regularly reviewed and updated by the HISTORY.com team. Articles with the “HISTORY.com Editors” byline have been written or edited by the HISTORY.com editors, including Amanda Onion, Christian Zapata, Cristiana Lombardo and Adrienne Donica.
Fact Check
We strive for accuracy and fairness. But if you see something that doesn't look right, click here to contact us! HISTORY reviews and updates its content regularly to ensure it is complete and accurate.
Citation Information
- Article Title
- The Great Northeast Blackout
- Author
- HISTORY.com Editors
- Website Name
- History
- Date Accessed
- October 29, 2026
- Publisher
- A&E Television Networks
- Last Updated
- May 27, 2025
- Original Published Date
- March 04, 2010