20 DEADLIEST Mistakes in Human History

Name: 20 DEADLIEST Mistakes in Human History
Uploaded: 2025-11-15T21:00:00-05:00
Channel: Joshua Garvin
Description: From catastrophic military campaigns to deadly political decisions, history is littered with fatal errors. Join us as we explore the most devastating mistakes that cost millions of lives! Our countdown includes the Halifax Explosion, Hitler's invasion of Russia, Mao's Great Leap Forward, and more blunders that altered the course of history forever.

VOICE OVER: Rebecca Brayton
WRITTEN BY: Joshua Garvin

From catastrophic military campaigns to deadly political decisions, history is littered with fatal errors. Join us as we explore the most devastating mistakes that cost millions of lives! Our countdown includes the Halifax Explosion, Hitler's invasion of Russia, Mao's Great Leap Forward, and more blunders that altered the course of history forever. We examine how Stalin's Terror Famine killed millions in Ukraine, how a wrong turn triggered World War I, and how the Taiping Rebellion became the bloodiest civil war in human history. Which deadly historical mistake do you think had the most devastating consequences? Let us know in the comments below!

#20: Halifax Explosion (1917)
#19: The Soviet Invasion of Afghanistan (1979)
#18: Escalation in Vietnam by LBJ (1965-68)
#17: Battle of Teutoburg Forest (9 C.E.)
#16: The Irish Potato Famine (1845-52)
#15: Japan Attack on Pearl Harbor (1941)
#14: The Failed Mongol Invasions of Japan (1274-81)
#13: The Spanish Armada (1588)
#12: The Fourth Crusade (1202-04)
#11: Russia Invades Ukraine (2022-)
#10: The Wanggongchang Explosion (1626)
#9: American Invasion of Iraq (2003-11)
#8: A Mistranslation May Have Caused America's Nuclear Attacks (1945)
#7: Moctezuma II Welcomes the Spanish (1519)
#6: The Wrong Turn That Triggered WWI (1914)
#5: Insulting Genghis Khan (1218)
#4: The Taiping Rebellion (1850-64)
#3: Stalin's Terror Famine (1932-33)
#2: Hitler Invading Russia (1941)
#1: Mao's Great Leap Forward (1958-62)

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Tags:

deadliest historical mistakes, Halifax Explosion, Soviet invasion of Afghanistan, Vietnam War escalation, Irish Potato Famine, Pearl Harbor attack, Mongol invasion of Japan, Spanish Armada, Fourth Crusade, Russia Ukraine invasion, Hiroshima bombing, Aztec Empire fall, World War I, Genghis Khan, Taiping Rebellion, Hitler Russia invasion, Mao Great Leap Forward, Iraq War, Wanggongchang explosion, historical disasters, watchmojo, watch mojo,