"Frank Ferdinand, the Archduke of Austria-Hungary, is assassinated with his wife by Serbian nationalist Gavrilo Princip."
"Following this assassination, Austria-Hungary declares war on Serbia, which leads other nations (Germany, Russia, France, Britain, Belgium) to enter the conflict as well, through their respectives military alliances."
"At Christmas, on the Western front, French, German, and British soldiers crossed trenches to exchange seasonal greetings and food."
"Britain & France launched a naval attack on Turkey in the Dardanelles, in order to take control of this strategic position. This resulted in a heavy military failure and was a serious blow to Winston Churchill, in the Allied war command, who was a long proponent of this assault."
"During the submarine warfare, German U-Boat torpedoed the Lusitania, a civilian cruiser, which resulted in 1,198 casualties. This event turned public opinion in many countries against Germany."
"This was the longest and largest battle of WWI, involving France and Germany on the Western front. It lasted 303 days and resulted in nearly 715,000 casualties - one of the bloodiest battle of history."
"To relieve the French on the Verdun front, Britain joins France against Germany in the Battle of the Somme. This was another of the bloodiest battle with nearly 1 million casualties on all sides."
"The telegram was an offer from Germany to Mexico to join war. This was intercepted and decoded by British intelligence, who had to ruse to reveal it to the US without disclosing they had broken the German codes - an early occasion on which intelligence influenced world events."
"Following this telegram, President Woodrow Wilson asked Congress for “a war to end all wars” that would “make the world safe for demoracy”, which was voted and approved."
"The treaty w as signed by the new bloshevik government of Soviet Russia with the Central Powers (Germany, Austria-Hungary, Bulgaria, Ottoman Empire), defaulting the Alliance to deal with the Russian Civil War."
"The Armistice was signed at the 11th hour between the Allies and Germany, end a conflict of 4 years, which resulted in 18 million deaths and 23 million wounded."
"Exactly 5 years after the assassination of Frank Ferdinand, the peace was signed between nations at Versailles. The treaty was an humiliation for Germany, which had economic consequences on the country."