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Schlieffen Plan and the First Battle of the Marne

Created by Sal Khan.

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  • leaf green style avatar for user Guilherme Lucas Barcelos
    How does the new technologies in warfare influenced the outcome of the Schlieffen Plan and eventually the war in trenches?
    (7 votes)
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    • leafers ultimate style avatar for user Andris
      At the beginning of the war most leaders thought that their troops have higher mobility, and thought with higher mobility they could put an end to the war quite fast. The new technologies, however, rather supported the defending armies. Think of, for example, the newly invented machine gun. It could not be carried around like the machine guns of today, it had to be installed at a spot before battle, so attacking armies could not use it. The new trench warefare also helped the side that was defending, and it was never just breaking the trench line at a place, there were dozens of them after one another, and it was impossible even with immense losses to break through the trench lines (not that the Germans or the French spared their soldiers, they definitely tried to break the enemy's trenchline system).

      By the end of the war both sides invented new technologies (mustard gas, tanks), but these had to be further developed to effectively work, so these did not really change the nature of the war.
      (34 votes)
  • male robot hal style avatar for user Carl Starvaggi
    I don't understand something. Why did Germany declare war on France in the first place? I mean, Russia's troop building up on the border on its western border was why Germany declared war on Russia, but what about France? What did they do to anger Germany?
    (8 votes)
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    • aqualine ultimate style avatar for user Ryan Chandler
      WWI Germany, lead by Bismark wanted to expand. Yes, Russia had troops on the Eastern front but A.) France was pretty weak, at least, compare to Germany and therefore a war on both sides was thought to be a smart decision and B.) Germany wants France, they want to expand and have Germany rule over the whole of the Earth, so they had to start somewhere. I understand your confusion because this was a terrible idea, thankfully. Germany's forces were spread thinly making Russia's large army time a lot easier on the Eastern. Bismark is well renowned for his great knowledge in warfare, but this was what really marked the downfall of the second Reich. Good question. I hoped this helped. If you have any more questions I'd be glad to answer them. Stay curious.
      (11 votes)
  • purple pi purple style avatar for user mechareb000
    Around , it said that the Germans marched right through Belgium. Why weren't they stopped by the citizens of Belgium?
    (6 votes)
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  • hopper cool style avatar for user wfolk
    I thought that the schlieffen plan called for the Germans to go further west and to encircle Paris than what Sal showed. Do the germans change the plan or I am wrong?
    (4 votes)
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    • piceratops ultimate style avatar for user kusai.contractor
      The Schlieffen Plan was needed because the Germans couldn't afford to fight the French on the Eastern Front and the Russians on the Western Front at the same time, fore they would be overpowered.

      So then the Germans decided that they could fight and defeat the French while the Russians were getting their troops ready

      So to answer your question the Germans did not go as far into French territory because then the troops in the east would get the responsibility of holding off the Russians for longer. The farther that the Germans go into France,the longer the distance is to the east so the Germans can get reinforcements

      So basically the Germans didn't want the chance of their eastern troops to get defeated before reinforcements got there
      (6 votes)
  • hopper jumping style avatar for user Spencer
    In the trench warfare, didn't they call that no man's land? At least that's what I heard.
    (3 votes)
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  • ohnoes default style avatar for user asinha4868
    Why did the Germans not attack France through Alsace and Lorraine?
    (3 votes)
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  • leaf blue style avatar for user Zain
    If Germany didn't go through Belgium and went straight through the middle of France then couldn't Britain have joined the side of Germany as they were old enemies with France. Germany did have stronger forces than France.
    (2 votes)
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    • aqualine seed style avatar for user Rachel
      France and Britain, after years of disputes and disagreements, had decided to make peace with each other by signing the Entente Cordiale in 1904. This agreement essentially meant that they would side by each other if war were to come to Europe (which it did), and not oppose each other. Both countries realized that the other was powerful, and that fighting each other would be futile. Besides, a pleasant relationship allowed both parties to benefit greatly. Another good reason for the alliance was to keep the growing powers of both Germany and Russia in check, because both countries were threatening the balance on power in Europe. (Russia eventually joined the Triple Entente to side with France and Britain as well).

      As for the Germans and the Schlieffen Plan, the main reason they didn't directly cross the border and attack France was that it was too dangerous and risky. The French knew the Germans were slowly growing in power and were prepared for an attack. For this reason, the border between the two countries was strongly fortified with many French troops, and victory there would be unlikely and would also take quite some time. So, they went with the plan to invade Belgium, hoping to enter France through the neutral country and make their way to capture Paris while the majority of French troops were still stationed by the border area.

      The problem here was that Germany didn't count on the Belgians putting up a fight, which they did. This slowed them down very much, and allowed the French troops to make their way to the Belgian side. Moreover, Britain had close ties to Belgium as well, and saw the need to get involved in the war. When the German troops finally managed to get through Belgium and made their way into France, the French troops were ready for them. They were not able to capture Paris, and so the front was established and war began.
      (5 votes)
  • winston default style avatar for user Creeper
    Why was "no man's land" called "no man's land"?
    (3 votes)
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  • aqualine ultimate style avatar for user yann
    What do you mean by ribs
    (2 votes)
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  • primosaur ultimate style avatar for user Yellow Shiƒt»
    At , how do you actually pronounce "schlieffen"?
    (2 votes)
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Video transcript

Ever since the Franco-Prussian War in 1870 to 1871, the Germans recognized that they were likely to face another war with France. That was the war that allowed Germany to unify. They humiliated France. They were able to capture some very valuable territory from France, in particular Alsace and Lorraine, which is very mineral rich. And so the Germans were plotting too, well, what are we going to do if we get into another war with them? At the same time, once France and Russia had this alliance, Germany fully recognized if there is a war with France, it's likely to not be just with France. It's likely to be a two front war. On the Western Front, they'll be in conflict with France. And on the Eastern Front, they'll be in conflict with Russia. And so to deal with this eventuality-- this is all the scheming that Germany did in the decades going up to World War I-- they came up with the Schlieffen Plan. And I'm sure I'm mispronouncing it. Named for Alfred von Schlieffen, he was chief of the German Empire's general staff from 1891 to 1905. And it was based on how do you deal with a two front war? And the general ides here were that Russia had a large and almost inexhaustible army. But because it was so large it would take a long time for it to mobilize. And the Germans are actually able to approximate it correctly because this is how long it did take the Russians to mobilize at the beginning of World War I. They estimated that it would take them about six weeks. So the Schlieffen Plan called for enough German troops on the Eastern Front, initially, in order to keep the Russians at bay. But then the main fighting force of the Germans, while the Russians are mobilizing, is to go after France and try to essentially knock France out of commission, so that they're not facing a two front war anymore. And then have those troops go back to fight against the Russians. And the way that they wanted to do it is by rolling through Belgium in a wheel like pattern like this. And the reason why they wanted to do this wheel like pattern is that they correctly predicted that the French were very eager to get this territory right over here. And the French actually had a plan-- they called it Plan 17- for going after Alsace and Lorraine. It was an offensive plan. And the view is if the French army is going in that direction, if the German army rolls through Belgium and is able to get them from the rear, they could put the French army out of commission. So in early August 1914, the Germans, once they declared war on France and on Russia, the Germans tried to put the Schlieffen Plan into action. And they frankly, almost succeeded. So through August and early September, the Germans were able to essentially roll through Belgium and keep the combined, mainly French forces, but there was also some assistance from British, to keep them on their heels. And this happened all the way until early September when they get near the Marne, or a little bit past the Marne River in France. And it was here that the Sixth French Army-- and when we talk about armies we're talking about huge numbers of troops. The Sixth French Army had over 200,000 troops in it. When we're talking about the Battle of the Marne-- which I'm about to talk to you. We're talking about the first Battle of the Marne. We're talking about a battle that involves two million troops. So these are battles that are occurring on an epic scale. Just each of these armies-- this army or this one, or even the German armies-- we're talking about tens to hundreds of thousands of troops. In general, an army characterize you're talking about over 50,000, 60,000 troops. So what happens as you go to early September, especially September 5, 1914, the Sixth French Army recognizes a mistake that the First German Army made. By trying to roll around like this, they exposed their right flank. So right over here would be the right flank of the German army. And just as most mammals, our flanks are our weak spot, that area between your ribs and your hips, the same thing is true for armies. The front of the army tends to be where you have the strongest forces. And then you have your supply routes going back. So if you can outflank an army-- and that's what a lot of military strategy is designed around-- you can hit an army in its weaker points. So by September 5, the First German Army recognized this, but it was too late. By September 6, they were essentially being confronted by the Sixth French Army. And by essentially turning to meet them they created an opening between them and the Second German Army. And that opening was able-- the French and the British were able to take advantage of that to essentially put the Germans on their heels after a month of advancing. And so right over here, you have the various French armies. And they were assisted by the British expeditionary force. And so from the Battle of the Marne, which was essentially, most historians would say, between September 6, or September 5, September 6 and September 12, they were able to put the Germans on the retreat. The Germans retreated past the Aisne River. And then once you get into November and the end of the year of 1914, the Germans essentially entrenched themselves. They were literally building deep trenches in northern France and a little bit of western Belgium. And what I have right over here-- let me see if I can draw it. What I have right over here, what the boundaries are eventually happened after the Germans suffered, essentially, their first big defeat. They had to retreat and they had to literally retrench. And this is what the borders would then be like. And these were literally trenches getting dug here. This first stage of the war was hugely dynamic. You had armies moving fairly rapidly over a period of weeks and months. But then once the Germans retrenched, you have roughly this position being static for the next three years and the famous trench warfare of the Western front that you might have seen movies on. And I want to emphasize this was a big deal. The first Battle of the Marne-- sometimes it's called the Miracle of the Marne-- if the French, with British help, were not able to push the Germans back, they might have accomplished the Schlieffen Plan and actually maybe would have won World War I, or at least been able to win the Western front fairly quickly. And then been able to deal with the Russians a little bit better. But because of the Miracle at the Marne-- which was hugely bloody. We're talking about 500,000 casualties on both sides. We're talking 100,000 to 200,000 dead on both sides. But because of that, that was able to hold off the Germans. But it got the Western front into this ugly three year long trench warfare.