✔ 最佳答案
After the Franco-prussian War,France was punished harshly,she ceded Alsace-Lorraine to Germany(Prussia).Germany was afraid that France would ally with countries to revenge.Thus,Germany signed the Three Emperors League.However, Franz Joseph(Austria-Hungary)discorded with Alexender II(Russia).Germany supported Austria-Hungary,so the Three Emperors League was destroied,Germany sigded the Triple Alliance to defend France.In1914, Sarajevo assassination was happened.Austria got German unconditional support(the blank cheque).Austria sent an ultimatum to Serbia on 23 July.Serbia rejected Austrian demand.Austria invaded Serbia. Russia and France supported Serbia and sent soldiers. Germany also sent soldiers to support Austria. Germany designed the Schlieffen plan.
The Schlieffen plan said that Germany got across Belgium to invade France firstly and then defended Russia. Germany invaded Belgium which destroied the Treaty of Lonton. Owing to maintain Belgium, Britain sent soldiers to helped France.
The Schlieffen plan leaded to the WW I outbreak directly.