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Current time:0:00Total duration:7:18

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.