The Royal Navy begins its naval blockade of Germany, leading to major food and material shortages later on. However, due to the 1839 Treaty of London guaranteeing Belgian neutrality, Great Britain intervenes and it brought onto the Allied side. Germany, keen on capturing Paris in order to knock France out of the war as fast as possible, executes the Schlieffen Plan by invading Belgium in an effort to bypass the Séré de Rivières fortification system along the German-French border. France enters the war two days later due to their alliance with Russia. With full German support, Austria-Hungary declares war on Serbia, followed by Germany declaring war on Russia on August 1 st when the latter refuse to stop the mobilization of their army. Austria-Hungary sends an ultimatum to Serbia, the contents of which are deliberately made unacceptable to the Serbs, while the German chancellor Theobald von Bethmann-Hollweg promises Austria a 'blank cheque' of unconditional support in case of war with Serbia.Īfter a month of failed attempts to deescalate the crisis, the great powers of Europe break into open conflict, triggering a chain reaction of war declarations. While visiting Sarajevo on the 28 th of June, Archduke Franz Ferdinand and his wife Sophie are assassinated by Serbian nationalist Gavrilo Princip, a Black Hand agent with secret ties to the Serbian armed forces, triggering the July Crisis. Assassination of Archduke Franz Ferdinand
