Medina, an Islamic holy city in Arabia, underwent the longest siege during First World War. The city of Medina was at the time part of the Ottoman Empire. The Ottoman Empire joined the war on the side of the Central Powers under the leadership of a nationalistic faction known as the Young Turks, despite the opposition of the last Ottoman caliph, Abdulhamid II. In an attempt to weaken the Ottomans, the Allies provoked an Arab Revolt within the empire led by Sharif Hussain of Mecca. Sharif Hussain, supported by British and French agents, occupied Mecca and later besieged Medina. The second holiest city in Islam was then guarded by an Ottoman battalion led by Fahreddin Pasha, who resisted for two years and seven months. The persistent defense that lasted even after the war had ended, was much celebrated as a heroic struggle to preserve the Caliphate and Islamic unity. Background In November 1914, British diplomats made contact with Sharif Hussain of Mecca, which would then be a two-year dialogue also known as the McMahon–Hussein Correspondence. The British offered materiel support in exchange for Sharif Hussain to switch allegiance to the Allies and stage a revolt with a promise of a future Hashemite Caliphate from Aden to Aleppo under British protectorate. With increasing fears that Ottomans were clamping down on subversive Arab nationalists, Sharif Hussain staged a region-wide revolt in June 1916. The prime objectives of the initial revolt was to deprive the Ottomans of any legitimacy to the title of Caliphate by capturing the two holy cities of Mecca and Medina. The Arabs began to capture Mecca against the surprised but well-equipped Ottoman defenders and culminated in the Battle of Mecca. Once Mecca is captured, the Arabs turned their attention to Medina, which was defended by an even bigger Ottoman force complemented by the strategic Hejaz Railway. Siege The siege began in October 1916 when the Arabs led by Hussein's son Faisal were repulsed with heavy losses by the Ottomans, who were fortified and armed with artillery in contrast to the mobile irregular Arab force. This would prove detrimental as the Ottomans reinforced the city of thousands of soldiers with necessary supplies. The Ottomans tried to recapture coastal ports that were used to supply the Arabs, but were foiled by the Royal Navy. At this point, Arab and Allied planners decided to lay siege to Medina instead of forcefully breaching