In 1914 Britain and the Ottoman Empire agreed on the ‘Violet Line’, linking the southern end of the Blue Line (1913) with the border between the Yemen Vilayet and the Aden Protectorates. This completed the formal partition of the barren Rub’ al Khali, or ‘Empty Quarter’, of the south-central Arabian peninsula between the two powers.in wikipedia
The Ottoman Empire concluded a treaty with Ibn Saud of Nejd, recognizing Saud as the hereditary Wali of the Vilayet of Nejd in return for Saud’s pledge not to involve himself in foreign affairs or grant concessions to foreigners. Ibn Saud also agreed to participate in any wars the Ottoman Empire might wage, however he would quickly retract all obligations to the Ottomans after World War I broke out.in wikipedia
On 28 June 1914 Archduke Franz Ferdinand, heir presumptive to the Austro-Hungarian throne was visiting Sarajevo, capital of Bosnia-Herzegovina, when the imperial entourage was disrupted by a bomb attack. Later that day Franz Ferdinand and his wife traveled to visit those injured by the blast, but were both shot and mortally wounded when their chaffeur unwittingly stopped in front of the assassin Gavrilo Princip—a 19-year-old Bosnian Serb revolutionary who wanted to unite Bosnia with Serbia in a Yugoslav state. As the conspiracy to kill the Archduke had been orchestrated by members of the Black Hand secret society—an organization linked to the Serbian Army—Austria-Hungary held Serbia responsible for the attack.in wikipedia
On 28 July 1914 the Austro-Hungarian Empire declared war on the Kingdom of Serbia, in response to Serbia’s rejection of Austria-Hungary’s July Ultimatum. In the following days, Russia, Germany, France, and Britain all entered the conflict, resulting in the First World War.in wikipedia
Alerted of Russian mobilization against Germany, Kaiser Wilhelm II ordered German mobilization and declared war on Russia. As per the Schlieffen Plan, Germany immediately prepared for the invasion of Luxembourg and Belgium on the assumption that France would enter the war. Although the British proposed that they would stay neutral if Germany did not attack France, the Kaiser was unable to get his generals to agree to this request as pausing the invasion was technically impossible.in wikipedia
On 2 August 1914 Germany occupied Luxembourg and sent an ultimatum to Belgium, demanding passage through the country. When Belgium refused, Germany declared war on France on 3 August and on Belgium the following day. German troops immediately crossed the border, launching an offensive against the Belgian city of Liège.in wikipedia
In response to the German invasion of Belgium—whose neutrality was safeguarded by the 1839 Treaty of London—the United Kingdom declared war on Germany, bringing the British Empire into World War I.in wikipedia
