Who: Gavrilo Princip vs. Franz Ferdinand
What: A Serbian nationalist and a member of the underground organization the Black Hand, Gavrilo Princip assasinated the heir to the Austro-Hungarian throne, causing A-H to declare war on Serbia. This is widely regarded as the trigger of the war.
Italy also delcares its neutrality on this day.
Serbia also declares war on Germany this day.
Who: French and British (Canadians) vs. Germans
What: This battle was widely regarded as first use of chemical warfare (chlorine gas). This was also the only German offensive of 1915.
Where: Ypres, Belgium
Who: British and French vs. Ottomans and Germans
What: Allies wanted to open a supply route to the Russians so the Eastern Front could put more pressure on the Central Powers and thus draw soldiers away from the Western Front. It ended suprisingly as a victory to the Ottomans, who were outnumbered and outsupplied. This campaign is notorious for terrible conditions (heat, disease, lack of supplies).
Where: Gallipoli Peninsula, Ottoman Empire
Who: German U-boat vs. Neutral Passanger crusier (This is debatable. The cruiser was carrying war supplies but she was carrying civilians as well, who were only making the journey from New York to Liverpool)
What: The RMS Lusitania was torpedoed by a German submarine, unfortunetely before ships knew how to defend themselves against such suprise attacks. The sinking was a key factor in American involvement.
Where: North Atlantic Ocean, near Ireland
Who: Austro-Hungarians vs. Italian
What: There were 12 individual battles, with extremely high casualty rates; half of the casualties of the Italian army were at Isonzo. Italy switched sides because they were threatened by Austria-Hungary when it invaded Turkey. They were promised more land and priviligies by the Allied Powers anyway, so they eventually fought against Austria-Hungary.
Where: Isonzo River, Eastern Italian Border
Who: French vs. Germans
What: It was a major battle on the Western Front. The French were trying to defend Paris, their prized gem of a city. Flamethrowers were introduced into the war during this battle. It was one of the longest and most devastating battles of WWI, resulting in a French "victory". This battle showed the determination of the French as they made up for lost ground, fighting no matter the cost (which led to the multitude of casualties).
Where: Verdun-sur-Meuse, France
Who: German submarines
What: When the French cross-channel passanger vessel the Sussex was torpedoed without warning, US President Woodrow Wilson said that if Germany continued this, Americans would enter the fighting. Fearing American involvement, the Germans introduced the Sussex Pledge, which stated that passanger ships would not be targeted, merchant ships would not be sunk until the presence of weapons were determined, and merchant ships would not be sunk without the provision for the safety of passsangers and crew.
Where: On and under the sea
Who: Royal British Navy vs. Imperial German Navy
What: It was the only naval battle and full-scale clash of battleships in World War I. It was an ambush on the Germans as they attempted to break Britain's blockade by Britain. It ended in continued British control of the North Sea but indecisive victory for both sides.
Where: North Sea, Denmark
Who: Russia vs. Central Powers
What: This was Russia's attack on the Eastern Front, known as their greatest contribution to the war and Austria-Hungary's "worst crisis". It worked in the sense that it forced Germany to pull forces from Verdun. It also caused so many casualties in the Austro-Hungarian army that it could never mount attack alone again.
Where: Modern-day Ukraine
Who: British and French vs. Germans
What: This is one of the largest battles in World War I with over a million casualties, making it one of the bloodiest conflcts in recent military history. The first day of the battle was incredibly devastating for the British as it still remains as one of the bloodiest battles in British military history. It was indecisive in conclusion; Germany retreated, leaving the French and British with both tactical and geographic advantages.
Where: Around the Somme River, France
Who: Germans (submarines)
What: Germany, believing the war had to be won before the US joined it, resumed the prctice of unrestricted submarine warfare. Both this resumption and the Zimmerman Telegram ironically led to US involvement.
Where: Under and on the sea
Who: German telegram to the Mexicans intercepted by the British and given to the Americans
What: The telegram was sent to Mexico from Germany to attempt to get the Mexicans to attack America so they had to use their forces at their border instead of sending them to Europe and subsequently the Allies. It was intercepted by the British and decoded. Then, it was sent to the Americans and was a driving cause of their involvement in the war.
What: Nicolas II abdicated after Russians decided that the multiple failures and shortcomings of the army during World War I were of enough magnitude to merit a revolution. These revolutions paved the way for the formatin of the USSR and the peace talks between Germany and Russia.
Who: British (Egyptian) vs. Ottomans
What: This was a back and forth series of three battles which ended in high casualties for both sides. The goal was similar to that of the Gallipoli campaign; to open up supply lines to Russia. The Ottomans were too well entrenched and thus did not move.The British withdrew after the Ottomans brought in more reinforcements.
Where: Gaza Strip, South Palestine
Who: French vs Germans
What: The battle was a French attempt to gain a piece of German-held land. It was advertised as an easy victory as the Germans were supposed to be "exhausted" from the Battles at Verdun and Somme. This battle ended in a disgraceful French loss, leading to mutinies within the French army and a general loss of hope.
Where: France (Between Soissons and Reims)
Who: Russians and Central Powers
What: An armstice was made between Russia and the Central Powers, freeing troops to go the Western Front and participate in Germany's last ditch effort, the Spring Offensive.
Who: Germans vs. Allied Powers (British and French, mainly)
What: The Germans knew the Americans would provide a serious advantage to the Allied Powers (enough to make them lose a war) so they decided to attack and attempt to finish the war before Americans could get to Europe. The Germans, however, were unable to maintain their advance as supplies and troops were unable to catch up to their fast-moving attacks.Eventually, German manpower was exhausted and they were finally outnumbered on the Western front.
Where: Northern France and Flanders, Belgium
Who: Allied Powers vs. Germans
What: This battle is sonsidered "the beginning of the end of the Great War". This decisive Allied victory set off a string of relentless Allied attacks, leading to the end of the war. The German attack did not work, leading to a devastating counterattack by the Allies.
Where: Marne River near Paris, France
Who: Leaders and diplomats from all around the world
What: This conference was an meeting of the victorious Allies to decide the consequences from the defeated Central Powers. This conference set up new borders and countries, introduced war guilt and high financial penalties for Germany specifically. The League of Nations was also created during this conference.
Who: Allied and Central Powers
What: This treaty ended the state of war between the Allied Powers and Germany. It was a major turning point in the war as officialy no more conflict, social or any other form, would be done. One of the conditions was that Germany had to take blame for the war.
Where: Palace of Versailles, France