Hi, I'm John Green, this is Crash Course World History and today we're going to talk about World War I. We actually have two videos about World War I. Today we're going to talk about how World War I happened. Next week we're going to talk about why. World War I is a really big deal. Especially to those of us who are really interested in like, industrialization and nation-states and modernity. So usually we don't talk that much about wars, but we're going to make an exception.

Mr. Green, Mr. Green, "Exception?" Cue the Mongol-tage.
Yeah, no me from the past. We don't roll the Mongol-tage every time we use the word exception, we roll it when we're talking about how the Mongols are an exception to a lot of our assumptions about civilizations.

Stan, Stan- There are no Mongols today, we are talking about World War I.

(Intro)

So I'm filming this in 2014, which means that the great war started 100 years ago and the World War I Centenary is just so hot right now, I can't miss out on it.

So most historians agree that the event that started World War I was the assassination of Austrian archduke Franz Ferdinand on June 28th, 1914, but beyond that, there's not a lot of agreement.

Others say the war really started after Franz Ferdinand bit it, like when Germany declared war or when Russia mobilized. So looking at why a war or any historical event happened means looking for a cause and effect relationship that implicitly assumes that if one particular event in a chain of events had gone differently, the historical outcome would also be different.

This is why we have alternate history novels. Right , like what would have happened in the American Civil War if the South had won the Battle at Gettysburg? What would have happened if the Nazis had repulsed the D-day invasion? In both cases, probably eventually the same outcome but that's neither here nor there.

The question we're looking at today is how. And that's a much more modest question because we can simply discuss a series of events but it's still a complicated one.

Because when you're talking about how, you're always picking from an uncountable number of things that happened. You know, a butterfly flaps its wings and that leads to a series of events and then eventually across the world an archduke gets killed.

So even when it comes to a relatively straightforward question like how, you'll never get to the bottom of all of it, but today we're going to discuss some of the how.

So one way or another, all wars start with a breakdown in peaceful relations between the eventual belligerents and World War I is no exception.

Oh, for the love of agriculture please stop it.

Right, but World War I is a bit unusual in that we have a concrete event and a date to start our discussion. Sometimes we get lucky, historically, and there's an invasion that starts a war like in the Korean conflict or the firing on Fort Sumter in the American Civil War.

But other times, it's much more butterfly effect-y with events that might or might not lead to a war, building upon each other until one side mobilizes or declares war or there's a fight over who shot first.

But here we have a specific assassination of a specific archduke, Franz Ferdinand in Sarajevo.

Now it wasn't a great day for Franz to visit Bosnia since it was the anniversary of the Serbs defeat at Kosovo Polje in 1389 and also St. Vitus's day, which was a celebration for Slavic nationalists and a Bosnian Serb named Gavrilo Princip and his co-conspirators chose to celebrate Slavic nationalism by killing Franz Ferdinand.

Now they didn't choose Franz Ferdinand at random. He was the heir apparent of the Austro- Hungarian Empire.

Franz Ferdinand wasn't particularly well liked, not by his uncle who was the head of the Austro-Hungarian Empire, certainly not by Bosnian Serb nationalists, also not really by everyone else in Europe except for the German Kaiser, but Franz Ferdinand was in his way kind of a moderate.

Oh it's time for the open letter. Oh look it's a collection of my favorite assassinated moderates. It's hard out there for a moderate.

An open letter to moderates:

Dear moderates, so one of the reasons that Franz Ferdinand's uncle didn't like him that much is that the emperor was really hardcore, whereas Franz Ferdinand, you know, he was kind of a moderate.

He was like you know, "I'm an Austro-Hungarian through and through but I see the Serbian argument."

Really, Franz Ferdinand was the one leader in the empire who might have come up with a solution to the problems of Serbian expansion and Bosnian independence. And murdering moderates has a way of making other moderates, you know, more extreme. In short moderates, your work may not be romantic, it may not appeal to the youth, but it is heroic and very dangerous.

Best wishes, John Green.

So even though Franz Ferdinand's uncle didn't particularly like him, as the emperor of Austria-Hungary, he felt a certain responsibility to, you know, do something. Otherwise the Serbian nationalists would feel like they could expand their territory at the expense of the empire, so despite what you often hear about World War I being pointless, this makes sense as a point sort of.

Now it's a bit of schoolyard bully kind of diplomacy, but it does make a certain sense, if Serbia can get bigger, then all of the other places will think that they can have have nations too. Soon enough, you don't have an empire.

Now there's still some debate about whether Princip and his fellow assassins acted alone or as part of a larger conspiracy organized by the Serbian government. But the Austrians certainly thought there was broader involvement which is why the whole thing ended up becoming a war.

So Princip was a member of the scary sounding Black Hand, a group dedicated to creating a greater Serbia that would include Bosnia and there's some evidence that the Serbian chief of military intelligence was in on the assassination plot or at least knew about it. In fact, it's likely that the bombs and pistols the assassins used were supplied by a Serbian army officer, but this is still pretty controversial so much so that people are currently fighting about it in comments.

So almost a month after the assassination, on July 23, Austria issued an ultimatum to Serbia. And Austria intentionally made the demands so harsh that the Serbs would inevitably have to reject them and ergo war, but that doesn't explain the month long delay.

What happened in that month? Well Austria's foreign minister, Berchtold, was afraid that if they attacked Serbia, Russia would then attack Austria-Hungary, so the Austrians spent that month talking to their ally, Germany to make sure the Germans would have Austria's back. The Austro-Hungarians got assurance on July 5th or July 6th in the form of what has been called the "blank check", a promise from Germany that they would help Austria if Russia mobilized. And it was clear that the Germans expected the Austrians to move quickly in response to the assassination, not like wait for another twenty days. So usually I don't care about dates, but at this point the timing becomes pretty important, let's go to the Thought Bubble.

So when the Serbs received the Austrian ultimatum, Russia declared itself to be in a period preparatory to war, which sounds a lot like mobilization but technically it wasn't, which Russia's foreign minister emphasized to the Germans.

The Tsar approved the measure on July 25th, and it went into effect on July 26th.

The Serbs rejected Austria's ultimatum on July 25th, but they made their rejection sound like a capitulation so the Germans thought that war had been averted. And they were kind of surprised then on July 28th when Austria suddenly declared war on Serbia even though the Austrian army wasn't actually ready to start fighting.

Then on July 30th, Russia exited its period preparatory to war and actually officially mobilized. Germany warned the Russians to stand down but two days later on August 1st, France mobilized it's armed forces in support of Russia and that same day, Germany mobilized and declared war on Russia.

So if you're keeping score at home - and good historians always do - Austria and Germany were the first to declare war on July 28th and August 1st respectively, but Russia with its pre-mobilization mobilization was actually ready to begin fighting before Serbia rejected Austria's ultimatum.

Anyway, then Germany declared war on France on August 3rd, marched through Belgium to invade, hoping to quickly knock out the French and focus on Russia. Sorry France but you know Russia's a big deal and you, you know.

German troops crossed Belgium's border on August 4th and the British issued an ultimatum to the Germans telling them to get out of Belgium or else. Germany chose "or else" and Britain declared war. So by August 4th, 1914, all the major powers involved in World War I were officially at war with each other.

Thanks Thought Bubble.

Now I know there were a lot of other powers that would get involved later including the United States, and Japan, and the Ottoman Empire -- even Italy.

But for the nations who did most of the actual fighting, Germany, Austria-Hungary, Russia, Serbia, France, Great Britain, the war happened both very quickly and very slowly.

Now looking back, it all happened almost at once but if you're in the middle of it, a month is a long time and at any point someone, like say the archduke, Franz Ferdinand, could have come in and said, "Wait a second."

Well I guess not anyone because he was dead.

But that's how an act of terrorism in a Bosnian city turned into the first major European war of the 20th century. A war that still resonates today. Now the Austrians and the Serbs probably both imagined that the war could stay localized to the Balkans especially since there had been previous conflicts in the region that hadn't blown up into a world war.

You know, like in 1908 and 1912 and 1913. We'll get into what made 1914 different next week.

The "whys" of course will always be very complicated, but for now please remember that we are always in the middle of a "how." Those living in June and July of 1914 could never have imagined how significant that month would be for human history and when thinking about them, it's worth remembering that we also can't imagine what our decisions today will mean in 100 years.

Thanks for watching. I'll see you next week.

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