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Video transcript

One of the reasons that's most cited as to a cause or the cause of why World War I turned into a world war, as opposed to just a regional conflict in southeast Europe, is the alliance system that was developing in the decades leading up to World War I. And to understand that, I've distilled a bunch of the alliances that occurred in those decades leading up to World War I. And this is just a distilled version. There were many other alliances that were tangentially related. But I tried to distill down the ones that were directly related to all of the dominoes falling in 1914 that led to all of Europe being essentially at war with each other. So to understand that, we have to rewind 75 years. So World War I starts in 1914. 75 years before that, in 1839, you have the Treaty of London. And the Treaty of London did many things. But Article 7 is what's relevant to the beginning of World War I, where Britain agrees to protect the neutrality of Belgium. And if you're skeptical, you might say, hey, this is a 75-year-old treaty. Why does this matter anymore? And that, actually, would be a good question. Really, all of these alliances-- it's a very healthy debate you can have as to whether these are the direct causes of why one of these powers declared war on the other. Or whether these were just excuses. These were a legal pretext for saying, oh, I need to declare war on you. When in reality, they really did want to declare war for a whole set of reasons to keep the other person's empire in check, to flex their military muscle, to go after more territory in their empires. Who knows what it might be? But needless to say, 1839 was the legal basis for the British Empire to protect Belgium. Now, you fast-forward 40 years, you get to 1879. You have a newly born German Empire out of the Franco-Prussian War in 1871. That newly born German empire, they just had-- essentially, it's an extension of Prussia, fundamentally, a German kingdom. They just had a war with France. They took some very valuable territory from France. They're paranoid that France wants to get back at them. They're paranoid about the Russians. And they have some connection with the Austrians-- the Austro-Hungarians, I should say. And so in 1879, they sign the Dual Alliance Treaty between Germany and Austria-Hungary to protect each other if Russia attacks. They have this common enemy right over here, Russia. So they are going to-- let me do this in a different color. They are going to protect each other. So this makes the new German Empire feel a little bit better about its position in Europe, in case they were to get into a war with either of these characters. Then in 1892-- you could imagine, if you ever play a game of Risk or if you ever play the game of Diplomacy, which is actually based on what happened in World War I. If you see some people that you might be at war with starting to become friends, you want to look for other friends, other alliances that you can form in case they declare war on you. So in 1892, you have an alliance between the French and the Russians, the Franco-Russian Military Convention. So this is an alliance. Let me do this in the magenta color again. You have an alliance between France and Russia. And then finally, in the early 1900s, 1904 to 1907, you have a series of agreements. "Entente" essentially means agreements. Agreements between the British Empire and France, between the British Empire and the Russian Empire, to essentially get on good terms with each other. These weren't as formally bonding that, hey, if someone's going to attack you, I'm going to attack them. But they were, essentially, able to resolve a lot of their issues on what's going on in their other imperial conquests. And they formed what is called the Triple Entente, the triple agreement between Britain, between the British Empire-- and right here, I just circled the United Kingdom-- France, and Russia. And on the other side of that, you had the Triple Alliance. You have Germany. You have Austria-Hungary. And you also have Italy. Now, the reason why, even though entering into World War I, Italy was formerly part of the Triple Alliance. And there were treaties between Italy and Germany to become part of this Triple Alliance. The reason I don't focus on those is once the war started, Italy did not go on the side of Germany and Austria-Hungary. It went on the side of the Allies, on the side of the Triple Entente. But this will give you a good background for why what would seem like a regional skirmish in southeast Europe turns into a pan-Europe and eventually pan-global war.