If you ask a classroom of students when did world war 2 end and start, you’re going to get a chorus of "1939" and "1945." It’s the standard answer. It's what the textbooks say. But history is actually a lot messier than those two clean numbers.
Honestly, the "start" of the war depends entirely on who you’re asking. If you’re in Beijing, the war didn't start in 1939. It started in 1937 with the Marco Polo Bridge Incident. If you’re in Prague, the nightmare began in 1938 with the Sudetenland. Even the end isn't just one day where everyone dropped their guns and went home for a beer. There were months of "ends" before the world finally stopped shaking.
The Official Kickoff: September 1, 1939
Most historians agree on September 1, 1939. That’s when Nazi Germany moved into Poland. This wasn't just another border skirmish; it was the "Gleiwitz incident" where Germans staged a fake Polish attack to justify a massive invasion.
Two days later, Britain and France declared war.
This is the date we use because it’s when the "world" part of World War II became undeniable. It triggered a domino effect of alliances. Before this, you had regional conflicts. After this, you had a global catastrophe.
Was it actually 1937?
There’s a massive argument to be made for July 7, 1937. That was the day of the Marco Polo Bridge Incident near Beijing. The Imperial Japanese Army and China’s National Revolutionary Army began a full-scale war that wouldn't stop for eight years.
Millions died.
To say the war started in 1939 is, frankly, a bit Eurocentric. If you were living in Nanking in 1937, the "World War" was already very much a reality. Historians like Rana Mitter, author of Forgotten Ally, argue that we can't understand the global conflict without acknowledging that the Asian front was burning long before the first Panzer crossed into Poland.
When Did World War 2 End and Start: The Long Finish of 1945
The end of the war is even more complicated. You’ve probably seen the iconic photo of the sailor kissing the nurse in Times Square. That was V-J Day. But there was also V-E Day.
And then there was the actual signing.
Germany surrendered first. That happened in May 1945. Adolf Hitler had committed suicide in his bunker on April 30, leaving Grand Admiral Karl Dönitz to try and save what was left of a crumbling Reich. On May 7, General Alfred Jodl signed the unconditional surrender in Reims, France.
The Soviet Union, however, wasn't satisfied.
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Stalin wanted his own ceremony. He insisted on a second signing in Berlin on May 8. Because of the time zone difference, it was already May 9 in Moscow when the news broke. This is why Russia still celebrates Victory Day on May 9, while the West celebrates on May 8.
The Pacific Theatre: A Much Darker Exit
The war in Europe was over, but the Pacific was still a bloodbath. It didn't truly end until the atomic bombings of Hiroshima and Nagasaki in August 1945.
On August 15, Emperor Hirohito did something unprecedented. He spoke to his people over the radio. Most Japanese citizens had never even heard his voice before. He announced the surrender, citing the "new and most cruel bomb" as a reason the war could no longer continue.
But even then, it wasn't "official" until September 2, 1945.
General Douglas MacArthur stood on the deck of the USS Missouri in Tokyo Bay. Representatives of the Japanese government signed the Japanese Instrument of Surrender. That 18-minute ceremony is the technical answer to when did world war 2 end and start.
Why the Dates Matter Today
Why do we care about these specific days? Because they shaped the entire map of the modern world.
The gap between the German surrender in May and the Japanese surrender in September allowed the Soviet Union to declare war on Japan and move into Manchuria and Korea. This directly set the stage for the Cold War and the eventual division of North and South Korea. If the war had ended all at once, the 20th century might look completely different.
There are also the "holdouts."
Hiroo Onoda, a Japanese intelligence officer, famously didn't surrender until 1974. He was hiding in the jungles of Lubang Island in the Philippines. He thought the reports of the war ending were just Allied propaganda. His commanding officer had to fly out to the island to personally order him to lay down his arms.
Key Milestones You Should Know
The timeline isn't just two dates. It's a series of escalations and de-escalations.
- September 1, 1939: Invasion of Poland (The traditional start).
- December 7, 1941: Pearl Harbor (When the U.S. finally entered).
- June 6, 1944: D-Day (The beginning of the end in Europe).
- May 8, 1945: V-E Day (Victory in Europe).
- August 6 & 9, 1945: Atomic bombs dropped.
- September 2, 1945: The formal surrender (The official end).
Some people even point to the 1931 invasion of Manchuria by Japan as the "true" start. It was the first major challenge to the League of Nations. The League failed to do anything, which basically told Hitler and Mussolini that they could get away with territorial expansion.
It was a slow-motion train wreck.
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Final Perspective
The question of when did world war 2 end and start is less about a calendar and more about human impact. For a Polish Jew, it started in 1939. For an American sailor, it started in 1941. For a Chinese civilian, it started in 1937.
We settle on September 1, 1939, to September 2, 1945, because those are the dates that encompass the highest concentration of global involvement.
Actionable Insights for History Buffs
If you want to truly understand this era beyond just the dates, here is what you should do next:
- Check Local Archives: If you have relatives who lived through the 1940s, look for their discharge papers or letters. You’ll often find that "the end of the war" for them was the date they were sent home, which was often months or years after 1945.
- Visit a "Time Capsule" Site: Places like the National WWII Museum in New Orleans or the Imperial War Museum in London provide the context of the "Phoney War" period between 1939 and 1940 where very little actual fighting happened in the West.
- Read Primary Sources: Look up the Potsdam Declaration. It’s the document that laid out the terms for Japan's surrender. Reading the actual language used by Truman, Churchill, and Stalin gives you a much better sense of the tension than any summary could.
- Acknowledge the Shadow Dates: Remember that the peace treaties weren't all signed in 1945. The Treaty of San Francisco, which officially ended the state of war between Japan and the Allied powers, wasn't signed until 1951. Technically, the Soviet Union (and now Russia) and Japan have still never signed a formal peace treaty due to disputes over the Kuril Islands. In that very specific, legalistic sense, the war never "ended" between them.
The 1939-1945 window is a helpful shorthand, but history is always deeper than a single line on a timeline.