Ottoman Army (1861–1922) in the context of "Cemil Cahit Toydemir"

The Hashemite Kingdom of Hejaz (Arabic: المملكة الحجازية الهاشمية, romanized: Al-Mamlakah al-Ḥijāziyyah Al-Hāshimiyyah) was a state in the Hejaz region of Western Asia that included the western portion of the Arabian Peninsula that was ruled by the Hashemite dynasty. It was self-proclaimed as a kingdom in June 1916 during the First World War, to be independent from the Ottoman Empire, on the basis of an alliance with the British Empire to drive the Ottoman Army from the Arabian Peninsula during the Arab Revolt.

The British government had promised Hussein bin Ali, King of Hejaz, a single independent Arab state that would include, in addition to the Hejaz region, modern-day Jordan, Iraq, and most of Syria, with the fate of the Palestine region (today's Israel and Palestine) being mentioned in more ambiguous terms. However, at the end of the First World War, the Treaty of Versailles turned Syria into a French League of Nations mandate and Iraq, Mandate Palestine and Transjordan into British mandates. Hashemite princes were installed as monarchs under the British mandates in Transjordan and Iraq; this became known as the Sharifian solution.

The Sayfo (Syriac: ܣܲܝܦܵܐ, lit. 'sword'), also known as the Seyfo or the Assyrian genocide, was the mass murder and deportation of Assyrian/Syriac Christians in southeastern Anatolia and Persia's Azerbaijan province by Ottoman forces and some Kurdish tribes during World War I.

The Assyrians were divided into mutually antagonistic churches, including the Syriac Orthodox Church, the Assyrian Church of the East, and the Chaldean Catholic Church. Before World War I, they largely lived in mountainous and remote areas of the Ottoman Empire and Persia, some of which were effectively stateless. The Ottoman Empire's nineteenth-century centralization efforts led to increased violence and danger for the Assyrians.

The Ottoman Committee of Union and Progress (CUP, also translated as the Society of Union and Progress; Ottoman Turkish: اتحاد و ترقى جمعيتی, romanized: İttihad ve Terakki Cemiyeti, French: Union et Progrès) was a revolutionary group, secret society, and political party, active between 1889 and 1926 in the Ottoman Empire and in the Republic of Turkey. The foremost faction of the Young Turks, the CUP instigated the 1908 Young Turk Revolution, which ended absolute monarchy and began the Second Constitutional Era. After an ideological transformation, from 1913 to 1918, the CUP ruled the empire as a dictatorship and committed genocides against the Armenian, Greek, and Assyrian peoples as part of a broader policy of ethnic erasure during the late Ottoman period. The CUP and its members have often been referred to as "Young Turks", although the Young Turk movement produced other Ottoman political parties as well. Within the Ottoman Empire its members were known as İttihadcılar ('Unionists') or Komiteciler ('Committeemen').

The organisation began as a liberal reform movement, and the autocratic government of Sultan Abdul Hamid II (r. 1876–1909) persecuted it because of its calls for constitutional government and reform. Most of its members were exiled and arrested after a failed coup-attempt in 1896 which started a period infighting among émigré Young Turk communities in Europe. The CUP's cause revived by 1906 with a new "Macedonian" cadre of bureaucrats and Ottoman army contingents based in Ottoman Macedonia which were fighting ethnic insurgents in the Macedonian Struggle. In 1908 the Unionists revolted in the Young Turk Revolution, and forced Abdul Hamid to re-instate the 1876 Constitution, ushering in an era of political plurality. During the Second Constitutional Era, the CUP at first influenced politics from behind the scenes, and introduced major reforms to continue the modernisation of the Ottoman Empire. The CUP's main rival was the Freedom and Accord Party, a conservative party which called for the decentralisation of the empire, in opposition to the CUP's desire for a centralised and unitary Turkish-dominated state.

The third siege of Missolonghi (Greek: Τρίτη Πολιορκία του Μεσολογγίου, often erroneously referred to as the second siege) was fought in the Greek War of Independence, between the Ottoman Empire and the Greek rebels, from 15 April 1825 to 10 April 1826. The Ottomans had already tried and failed to capture the city in 1822 and 1823, but returned in 1825 with a stronger force of infantry and a stronger navy supporting the infantry. The Greeks held out for almost a year before they ran out of food and attempted a mass breakout, which however resulted in a disaster, with the larger part of the Greeks slain. This defeat was a key factor leading to intervention by the Great Powers who, hearing about the atrocities, felt sympathetic to the Greek cause. Their support would prove decisive in helping the Greeks win the war and gain independence.

The 31 March incident (Turkish: 31 Mart Vakası) was an uprising in the Ottoman Empire in April 1909, during the Second Constitutional Era. The incident broke out during the night of 30–31 Mart 1325 in Rumi calendar (GC 12–13 April 1909), thus named after 31 March where March is the equivalent to Rumi month Mart. Occurring soon after the 1908 Young Turk Revolution, in which the Committee of Union and Progress (CUP) had successfully restored the Constitution and ended the absolute rule of Sultan Abdul Hamid II (r. 1876–1909), it is sometimes referred to as an attempted countercoup or counterrevolution. It consisted of a general uprising against the CUP within Istanbul, largely led by reactionary groups, particularly Islamists opposed to the secularising influence of the CUP and supporters of absolutism, although liberal opponents of the CUP within the Liberty Party also played a lesser role. Eleven days later the uprising was suppressed and the former government restored when elements of the Ottoman Army sympathetic to the CUP formed an impromptu military force known as the Action Army (Hareket Ordusu). Upon entering Istanbul on 24 April Sultan Abdul Hamid II, accused by the CUP of complicity in the uprising, was deposed and the Ottoman National Assembly elevated his half-brother, Mehmed V, to the throne. Mahmud Shevket Pasha, the military general who had organised and led the Action Army, became the most influential figure in the restored constitutional system until his assassination in 1913.

The precise nature of events is uncertain; differing interpretations have been offered by historians, ranging from a spontaneous revolt of discontents to a secretly planned and coordinated counter-revolution against the CUP. Most modern studies disregard claims the sultan was actively involved in plotting the uprising, emphasising the CUP's mismanagement of troops in the build up to the mutiny and the role of conservative religious groups. The crisis was an important early moment in the empire's process of disintegration, setting a pattern of political instability which continued with military coups in 1912 and 1913. The temporary loss of power led to radicalisation within the CUP, resulting in an increasing willingness among Unionists to utilise violence. Some scholars have argued that the deterioration of ethnic relations and erosion of public institutions during 1908–1909 precipitated the Armenian genocide. The crisis also represented the demise of the Sultanate's power in the Ottoman Empire, as a series of constitutional amendments confined its function in government to the confirmation of parliamentary decisions, conversely cementing parliament's supremacy in a significant step of republicanism in Turkish political history.

The German–Ottoman alliance was ratified by the German Empire and the Ottoman Empire on August 2, 1914, shortly after the outbreak of World War I. It was created as part of a joint effort to strengthen and modernize the weak Ottoman military and to provide Germany with safe passage into the neighbouring British colonies.

The Greco-Turkish War of 1897 or the Ottoman-Greek War of 1897 (Turkish: 1897 Osmanlı-Yunan Savaşı or 1897 Türk-Yunan Savaşı), also called the Thirty Days' War and known in Greece as the Black '97 (Greek: Μαύρο '97, Mauro '97) or the Unfortunate War (Greek: Ατυχής πόλεμος, romanized: Atychis polemos), was a war fought between the Kingdom of Greece and the Ottoman Empire. Its immediate cause involved the status of the Ottoman province of Crete, whose Greek-majority population had long desired union with Greece. Despite the Ottoman victory on the field, an autonomous Cretan State under Ottoman suzerainty was established the following year (as a result of the intervention of the Great Powers after the war), with Prince George of Greece and Denmark as its first High Commissioner.

The war put the military and political personnel of Greece to test in an official open war for the first time since the Greek War of Independence in 1821. For the Ottoman Empire, this was also the first war-effort to test a re-organized military system. The Ottoman army operated under the guidance of a German military mission led (1883–1895) by Colmar Freiherr von der Goltz, who had reorganized the Ottoman military after its defeat in the Russo-Turkish War of 1877–1878.

The Emirate of Nejd and Hasa was the second iteration of the Third Saudi State from 1913 to 1921. It was a monarchy led by the House of Saud. The state was formed after Saudi forces seized al-Hasa from the control of the Ottoman Empire garrison, during the Conquest of al-Hasa. It was the direct antecedent of the Sultanate of Nejd, and a legal predecessor of modern-day Saudi Arabia.