Ottoman entry into World War I

The Ottoman Empire's entry into World War I began when its navy carried out a surprise attack on Russia's Black Sea coast on 29 October 1914, following which Russia declared war on it on 1 November 1914. Russia's allies, Britain and France, then declared war on the Ottoman Empire on 5 November 1914. The reasons for the Ottoman action were not immediately clear, since the Empire was not formally allied with any of the great powers. This decision would ultimately lead to the deaths of hundreds of thousands of Ottomans and the eventual dissolution of the empire.

The Young Turk Revolution, which restored the Ottoman constitution of 1876 and reconvened the Ottoman parliament, effectively started the Second Constitutional Era. Young Turk movement members once underground (named committee, group, etc.) established (declared) their parties. Among them, the "Committee of Union and Progress" (CUP) and the "Freedom and Accord Party"—also known as the Liberal Union or Liberal Entente (LU)—were major parties. A general election was held in October and November 1908 and CUP became the majority party.

A myriad of Ottoman military reforms paved the way for the transformation of the Ottoman Classical Army into the Ottoman Modern Army that would see the combat of the First World War. During this period the Ottoman Army faced many challenges including the Italo-Turkish War (1911), the Balkan Wars (1912–13), unrest on the periphery (such as in the Yemen Vilayet and the Hauran Druze Rebellion), and continuous political unrest in the empire: the 1909 counter coup had been followed by a restoration, and then another coup d'état in 1912, which was followed by a raid on Porte in 1913. Thus, at the onset of the First World War, the Ottoman Army had already been involved in continuous fighting for the previous three years.

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