World War I: History Notes for UPSC Mains

World War I, also known as the Great War and First World War, was a deadly global conflict that originated in Europe. Beginning from 1914 and lasting until 1918, the First World War left with an estimated nine million combatant deaths and 13 million civilian deaths as a direct result of the conflict.

World War I is a topic covered in the world history segment of the UPSC Mains examination. As such candidates appearing for the exam will find the information from this article useful.

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Origins of World War I

Towards the end of the 19th century, the growing rivalry between European nations became all too apparent. Germany, upon its unification in 1871, was becoming an industrial power and other nations of Europe, specifically France and Britain, felt threatened by this.

Around this time the fracturing Ottoman Empire gave birth to new countries in the Balkan region. One of them, Serbia, was gaining land and power at the expense of the empire of Austria-Hungary. To counter this threat, along with any future ones, the Austro-Hungarian Empire formed an alliance with Germany and Italy to defend each other. 

In response, Britain, France and Russia formed the Triple Entente for the same purpose.

During the 1900s both Britain and Germany added bigger and better battleships to their naval arsenals. The rest of Europe also followed suit. By 1914, most of the European countries had their armies ready for war. All it needed was a spark to ignite it. That spark came when Archduke Franz Ferdinand was assassinated in Sarajevo, Bosnia on June 28, 1914.

Franz Ferdinand was the heir to the throne of Austria-Hungary and the man who shot him was a Serb nationalist, Gavrilo Princip. Gavrilo was protesting against  Austro-Hungarian rule in Bosnia. Austria-Hungary declared war on Serbia, prompting Russia to mobilize its army to defend Serbia. Germany, in turn, declared war on Russia and on France. To invade France a large German army marched through Belgium, violating its territorial integrity. This drew Britain into the war, since, in 1830, it had made an agreement to defend Belgium if it was ever attacked.

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The making of a Global War

The war drew in many European powers at the time along with their overseas colonies. They were divided into two groups – the Allied Powers and the Central Powers. The Central Powers were made up of Germany, Austria-Hungary and Turkey, while the Allies including France, Britain and its empire, Russia, Italy, Japan and from 1917, the United States of America. The war was fought along two main lines, or fronts. There was the Western Front, which ran from Belgium, through France to Switzerland, and the Eastern front which ran from the Baltic to the Black Sea. There were also sporadic fighting in the Middle East and along the border between Italy and Austria.

For a better understanding of the causes of World War I, we have given a table below outlining the events before and during the conflict for easy reference.

Events Before and During World War I

Year/Month Event
1878 Serbia gained independence from the Ottoman Empire
1881 Germany, Austria-Hungary and Italy form the Triple Alliance to defend each other in the event of war
1904 Britain forms the Entente Cordiale with France
1907 Russia Joins with Britain to form the Triple Entente
1908 Austria-Hungary Occupies Bosnia-Herzegovina to stop Serbia from taking control
1912-1913 Balkan Wars are fought between the Balkan League (Serbia, Bulgaria, Greece and Montenegro). The Balkan League is victorious
1914 – June 28 Gavrilo Princip assassinated Archduke Franz Ferdinand in Sarajevo
1914 – July 28 Austria declares war on Serbia. Russia prepares to defend Serbia from Austria
1914 – August 1 Germany declares war on Russia to defend Austria
1914 – August 3 Germany Declares war France, Russia’s ally
1914 – August 4 German armies march through Belgium to France. Britain declares war on Germany. World War I begins
1914 – August 26 Germany defeats Russian forces at the battle of Tannenberg
1914 – September At the battle of the Marne, the Allies halted the German advance on Paris. German victory in the same month ends Russian involvement in East Prussia.
1914 – November At the end of the battle of Ypres, German forces are prevented from itching the English Channel

What made World War I different?

The factor that made World War I different was the fact that it was fought from parallel lines of trenches separated from only a short stretch of ground known as “no man’s land”. Trench warfare was necessary as the power, speed and accuracy of the weapons used on both sides made open battle impossible. When soldiers did leave the trenches to launch an attack, often only a few metres of the ground was gained and the cost of casualties was enormous. This led to a stalemate situation that lasted from the end of 1914 until the summer of 1918. Even the use of new weapons such as tanks, nerve gas and aeroplanes did little to change the situation.

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The Tide Turns

At the end of 1917, following the Russian Revolution, Russia had started peace talks with Germany and German soldiers who had been fighting on the Eastern Front were able to join the fighting in the west, For a while, they outnumbered the Allied forces, but by 8 September 1918 over 1,20,000 well-trained and well-equipped forces of the United States joined the allies in France. This changed the balance power in favour of the Allies. By the End of October, all German occupied-France and Belgium had been reclaimed with Turkey and Austria-Hungary having been defeated.

Important Battles of World War I



1915 British naval blockade of Germany leads to a German submarine blockade of Britain
1915 – April – May Germany uses poison gas for the first time at the second battle of Ypres
1915 – May 22 Italy joins the Allies
1915 September British and French Campaign at Loos fails
1916 – February Start of the battle of Verdun, lasting for five months
1916 – March Failure of the Gallipoli campaign by Australian, New Zealand and British forces to knock Ottoman Turkey out of the war
1916 – June Russian offensive led by general Brusilov fails to defeat the Germans
1917 – April 6 The United States joins the war on the side of the allies
1917 – July The third battle of the Ypres, Allied forces gain little in their offensive
1917 – October Italians are defeated at the battle of the Caporetto by Germany and Austria-Hungary
1918 – March 3 Armistice signed between Russian and Germany
1918 – July Germany launches the offensive on the western front. The offensive fails and the allies launched a counteroffensive in August of that year which is a success
1918 – November Armistice is signed between Germany and the Allies in November !! at the 11th hour. End of World War I

End of the War 

In Germany, people were running short of food and fuel. The German navy mutinied and there was widespread unrest. On November 9, the German ruler, Kaiser William II, abdicated and on November 11. 1918 an armistice was signed between Germany and the allies, bringing the fighting to an end. In January 1010, the Allies met at the Paris Peace Conference, which formally ended the war. It drew up the Treaty of Versailles, which imposed a harsh peace upon Germany and laid the responsibility of starting the conflict squarely on Germany’s shoulders. 

World War I UPSC Notes – Download PDF Here

As part of the treaty, Germany was forced to give up its colonies overseas and vast sums of money to its former enemies. It also had to return Alsace-Lorraine to France. The wider implications of the treaty would be one of the causes of World War II.

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