Causes of WWI

No single issue above could have caused WWI, but combined tensions seemed insurmountable. A regional dispute in the Balkans after the assassination of the heir to the Austrian heir by a Serbian nationalist group morphed into a global conflict when European alliance systems forced nations to take sides. 

This assassination caused Austria to declare war on Serbia. Serbia’s ally, Russia, then declared war on Austria. Germany then wrote a “blank check,” promising unlimited support to Austria, and declared war on Russia. Finally, France and Great Britain joined the side of Russia through the Triple Entente. These complex interactions resulted in immense losses and disruptions for the victors and the vanquished. 

Source: Canadian History Class Website

Developments of WWI

Military Advancements

World War I led to a variety of new military technologies that confounded traditional strategies of warfare and led to massive troop losses: 

1. Tanks: First used by the British in the Battle of the Somme in 1916, tanks proved to be a powerful new weapon on the battlefield. They could cross trenches and barbed wire, providing cover for troops while they advanced.
2. Poison gas: Both sides used chemical weapons, with the Germans being the first to use chlorine gas at the Second Battle of Ypres in 1915. The use of poison gas resulted in over 1 million casualties.
3. Submarines: The Germans used submarines, or U-boats, to attack merchant ships. They were very effective at cutting off supplies to the British Isles, but the development of convoy systems and depth charges eventually made them less effective.
4. Aircraft: Military aircraft were used for reconnaissance and bombing, and later in the war, fighter planes engaged in dogfights. The development of fighter planes also made an impact on the war, as it allowed the allies to have air superiority in the later stages of the war.
5. Trench warfare: Both sides dug deep trenches to protect themselves from enemy fire. This led to a stalemate on the Western Front for most of the war, as neither side could make significant progress.

Global Conflict

The war in Europe quickly spread to non-European theaters, transforming the war into a global conflict.

Western Front

• During the Battle of the Marne, France stopped Germany from invading Paris. The German plan for war was called the Schlieffen Plan. Its goal was to sneak through Belgium and attack France, forcing them into submission before Germany had to deal with Russia.
• Trench Warfare involved a system of trenches dug into and under the ground. The space between each trench was called “No Mans Land,” as most who entered were killed by mines, machine guns, high-caliber weapons, or chemical gases. Life in the trenches was equally as dangerous, as many contracted diseases, such as gangrene, or were killed when the opposing trench advanced.

Eastern Front

• Russia and Romania held off advances from Germany, Austria-Hungary, and the Ottoman Empire. Transportation of supplies was made more efficient by the use of rail lines on each side.
• Conflict in the east ended in 1917 when the Russian Revolution’s new government signed the Treaty of Brest-Litovsk, concluding the war involving Russia.

The Armenian Genocide

The Armenian Genocide was a result of the political and social upheaval caused by World War I, as well as the collapse of the Ottoman Empire. The Ottoman government, under the leadership of the "Young Turks," used the war as an opportunity to rid the empire of its Armenian population. Armenians were forcibly removed from their homes and sent on death marches through the Syrian desert. Many were killed along the way, and those who survived were often interned in concentration camps. The Ottoman government also orchestrated mass killings and death squads to murder Armenians.

The Republic of Turkey has denied and still denies the fact of genocide and its responsibility for the crime.

The Easter Rebellion

The Easter Rising was a rebellion in Ireland that began on April 24, 1916, during World War I. It was organized by a group of Irish nationalists who sought to end British rule in Ireland and establish an independent Irish Republic. The rebellion was led by Patrick Pearse, James Connolly, and other members of the Irish Republican Brotherhood and the Irish Citizen Army.

The United States

The United States joined the war after being pushed to abandon its initial policy of isolation. Germany’s use of unrestricted submarine warfare and the sinking of the Lusitania had many Americans interested in joining the war efforts. However, the final straw was the Zimmerman telegram—Germany’s attempt at causing a Mexican invasion of the US southern border to keep them from entering the European conflict. 

Negotiating Peace 

Germany asked the French, British, and United States to negotiate an armistice to end the war. Germany had suffered mass casualties since the US entered the conflict, and they were unable to continue fighting due to extreme economic conditions. The Armistice was negotiated, as well as the Treaty of Versailles at the Paris Peace Conference in 1918.

The relationship between Europe and the world shifted significantly with the globalization of the conflict, the emergence of the United States as a world power, and the overthrow of European empires