Britannica LaunchPacks | World War I: Key Battles and Events World War I: Key Battles and Events For Grades 6-8 This Pack contains: 6 ARTICLES 8 IMAGES 2 VIDEOS © 2020 Encyclopædia Britannica, Inc. 1 of 60 Britannica LaunchPacks | World War I: Key Battles and Events World War I A major international conflict fought from 1914 to 1918, World War I was the most deadly and destructive war the world had ever seen to that time. More than 25 countries eventually participated, aligned with either the Allied or the Central powers. The Allies—who won the war—included primarily France, Great Britain, Russia, Italy, Japan, and, from 1917, the United States. The Central Powers consisted mainly of Germany, Austria-Hungary, and the Ottoman Empire (Turkey). World War I felled four great imperial dynasties, in Germany, Russia, Austria- Hungary, and Turkey. It led to revolution in Russia, destabilized Europe, and laid the foundations for World War II. (For a chronology of events for World War I, seeWorld War I Chronology.) Encyclopædia Britannica, Inc. An animated timeline covers the major events of World War I. Encyclopædia Britannica, Inc. A Maxim machine gun, belt-fed and water-cooled, is operated by German infantrymen during World War… Imperial War Museum © 2020 Encyclopædia Britannica, Inc. 2 of 60 Britannica LaunchPacks | World War I: Key Battles and Events Wounded German soldiers are treated at a field hospital during World War I. Encyclopædia Britannica, Inc. Learn about three notable women and their contributions in World War I: Marie Curie, Mabel St. Clair … Encyclopædia Britannica, Inc. On a human scale, the scope of the war was just as monumental. More than 65 million soldiers were mobilized for the armies, navies, and emerging air forces. Some 8.5 million lost their lives, and more than 21 million were wounded. In addition, civilian populations worked as never before to produce enormous quantities of guns, munitions, and other supplies. Because civilians played such an important role, World War I was the first conflict to be called “total war.” The Onset of War Austria's Archduke Francis Ferdinand and his wife, Sophie, sit in an open carriage in Sarajevo… World History Archive/ARPL/age fotostock © 2020 Encyclopædia Britannica, Inc. 3 of 60 Britannica LaunchPacks | World War I: Key Battles and Events Archduke Francis Ferdinand (Franz Ferdinand), the heir to the Austro-Hungarian throne, was killed in … Contunico © ZDF Enterprises GmbH, Mainz On June 28, 1914, Archduke Francis Ferdinand of Austria-Hungary was assassinated. He was murdered at Sarajevo, the capital of the Austrian province of Bosnia. The assassin was Gavrilo Princip, a Serbian-trained Bosnian terrorist. Austria claimed that Serbian government officials had trained and equipped Princip’s group, which was known as the Black Hand. For many years Serbia and Austria-Hungary had been unfriendly because Serbian nationalists wanted to unite all Slavic peoples living in the Balkan region into a single state. Slavs living in Austria-Hungary would be included, and Austria-Hungary strongly opposed this. Austria-Hungary decided to use the assassination as an excuse to settle its quarrel with Serbia. Germany promised to back Austria-Hungary. On July 23 Austria-Hungary presented a warlike ultimatum to Serbia, allowing only 48 hours for an answer. Serbia responded by July 25 but suggested that some of Austria-Hungary’s demands be referred to the other European powers. Austria-Hungary refused Serbia’s suggestion, and on July 28 it declared war on Serbia. All the nations in Europe had been expecting war. For many years rival groups of nations had been making treaties and alliances. By 1914 Europe had been divided into two camps. Germany, Austria-Hungary, and Italy were members of the Triple Alliance. Later, after the withdrawal of Italy and the addition of the Ottoman Empire, the Triple Alliance took a new name, the Central Powers. Russia, France, and Britain formed the rival Triple Entente. Later they were called the Allies. Except for Bulgaria, the Balkan states sided with Serbia and the Allies. These alliances were brought into action July 28 by Austria-Hungary’s declaration of war. Within a week all Europe was at war. Other Nations Involved On July 29 Russia mobilized its troops near the Austrian and German borders, purportedly to keep Serbia from being crushed. However, Russia had plans in the Ottoman Empire that had been blocked by Austria-Hungary and Germany. Russia wanted to control Constantinople and the straits from the Black Sea to the Aegean Sea. On July 31 Germany demanded that Russia stop its war mobilization measures and delivered an ultimatum to France to declare itself neutral in the event of war between Russia and Germany. France and Germany had been enemies in many previous wars. They had also been divided by the question of Alsace-Lorraine. Both Russia and France ignored the German demands. Fighting began on the German-Russian frontier on August 1. Germany declared war on France on August 3. © 2020 Encyclopædia Britannica, Inc. 4 of 60 Britannica LaunchPacks | World War I: Key Battles and Events Britain Declares War A World War I British or American Army soldier stands in uniform wearing a brodie helmet and an… © Comstock/Thinkstock Britain and Germany had been growing more and more unfriendly before 1914. Germany claimed that Britain was trying to keep it from becoming a world power. With the start of the war Germany made clear that it planned to invade France through Belgium. Britain, along with Germany and France, had signed a treaty in 1838 guaranteeing the independence and neutrality of Belgium. On August 4 Britain declared war on Germany to protect Belgian neutrality. The rest of the British Empire immediately prepared to send troops. Japan entered the war on the side of the Allies on August 23. Italy decided to remain neutral for the time being, despite its membership in the Triple Alliance. Many Italians favored joining the Allies, to help Italy obtain territories in Austria-Hungary in which people of Italian descent lived. © 2020 Encyclopædia Britannica, Inc. 5 of 60 Britannica LaunchPacks | World War I: Key Battles and Events The War During 1914 German infantry advance on the battlefield in France in August 1914. U.S. Department of Defense Wounded soldiers received treatment at a field hospital in France during World War I. Paul Thompson—FPG/Archive Photos/Getty Image All the major powers had war plans designed for quick victories but no plans for a long, drawn-out stalemate. The German Schlieffen Plan—named after Count Alfred von Schlieffen, a noted military strategist—was designed to avoid a long, costly war on two fronts. It called for the German left flank to hold the French army on the Rhine River. The right flank was to sweep through Belgium and northern France toward Paris, the French capital. After defeating France, the Germans then planned to quickly move these troops by rail to the east to defeat Russia. The French had agreed to respect Belgian neutrality. Therefore they could not go through Belgium to attack Germany. Instead they intended to concentrate their troops on the center and right flanks. They then planned to strike a blow against the Rhine front. The Russians planned to drive a wedge between Austria-Hungary and Germany. They then intended to make a direct attack on Berlin. Although all these war plans failed, the German Schlieffen Plan came close to succeeding. The right flank of the German army almost reached Paris but was thrown back by the French in the First Battle of the Marne, one of the few decisive battles of the war. © 2020 Encyclopædia Britannica, Inc. 6 of 60 Britannica LaunchPacks | World War I: Key Battles and Events French Defense on the Marne The Germans developed Big Bertha howitzer guns that smashed the Belgian and French forts in 1914. Marc Romanych The French army of about 4 million was practically equal in size to the German army. Only a third of the soldiers, however, were fully trained first-line troops. The French were not surprised that the Germans came through Belgium. What they did not expect was that the Germans would immediately use so many of their reserves as first-line troops. This gave the Germans more effective manpower. French and British troops met the attacking Germans at the Belgian frontier in August. The French were driven back at Charleroi. The British were driven back at Mons. The Germans forced both armies to retreat south. The Western Front lay generally east of the Marne River in France. It hardly wavered in four years. Encyclopædia Britannica, Inc. By the beginning of September a part of the German army was approaching Paris. Before the Germans were able to move past the city, however, the French attacked the exposed German right flank. They then advanced into a gap that this attack opened between two German armies. The French also counterattacked along the entire front. The First Battle of the Marne was fought September 6–10. The Germans, unable to gain a decisive victory, retreated some 50 miles (80 kilometers) north of the Marne River. Trench Warfare and Blockades © 2020 Encyclopædia Britannica, Inc. 7 of 60 Britannica LaunchPacks | World War I: Key Battles and Events Trench Warfare and Blockades A British soldier prepares for action in a trench on the Western Front during World War I. Hulton Archive/Getty Images With the hope of a short war now lost, the fighting on the Western Front settled down to trench warfare. Victories on the battlefield were soon being measured in yards, with enormous casualty rates. German machine gunners occupy a trench during World War I. Prints and Photographs Division/Library of Congress, Washington, D.C.