First Battle of Kosovo1389 CE

Kosovo Field, Kosovo

On 15 June 1389, Murad I's Ottoman army defeated a Serbian-led coalition under Prince Lazar Hrebeljanovic on the Field of Kosovo (Kosovo Polje). The battle secured Ottoman control over the Balkans and opened the road to further European expansion. Both commanders died: Lazar was captured and executed after the battle, and Murad I was assassinated — according to most sources — by a Serbian nobleman during or shortly after the battle. The outcome ensured Ottoman dominance in the Balkans for the next century. The battle became a foundational myth of Serbian national identity.

Battle of Ankara1402 CE

Ankara (Cubuk Plain), Turkey

On 20 July 1402, Timur (Tamerlane) defeated and captured Ottoman sultan Bayezid I at the Battle of Ankara (Cubuk/Chubuk Plain north of Ankara), inflicting the most devastating defeat in Ottoman history. Timur restored the Anatolian beyliks Bayezid had absorbed and temporarily dismembered the Ottoman state. Bayezid died in Timurid captivity in 1403, triggering an eleven-year civil war (the Ottoman Interregnum, 1402-1413) among his sons. The defeat delayed Ottoman consolidation and the conquest of Constantinople by approximately half a century. Mehmed I eventually reunited the empire in 1413.

Conquest of Constantinople1453 CE

Constantinople (Istanbul), Turkey

On 29 May 1453, Mehmed II's forces breached the walls of Constantinople using massive bombards cast by the Hungarian engineer Orban, ending the 1,100-year-old Byzantine Empire. Emperor Constantine XI Palaiologos died in the final assault. The conquest transformed the city into Istanbul, the new Ottoman capital, symbolizing the empire's rise as a world power bridging Europe and Asia. Mehmed II had the Hagia Sophia converted to a mosque and undertook systematic repopulation of the depopulated city. The fall of Constantinople sent shockwaves through Europe and is often cited as the conventional end of the Middle Ages.

Battle of Chaldiran1514 CE

Chaldiran, Iran (near Turkish border)

Selim I's gunpowder-equipped army defeated the Safavid Persians at Chaldiran on 23 August 1514, consolidating Ottoman control over eastern Anatolia and hardening the Sunni-Shia ideological divide. The Ottomans' superior artillery and disciplined Janissary infantry overcame the Safavids' cavalry-based army under Shah Ismail I, who was forced to flee and never again personally commanded an army in battle. The victory ended immediate Safavid threats to Anatolia and set the stage for Selim I's conquest of the Mamluk Sultanate the following year. The battle also hardened the Sunni-Shia confessional boundary that would define Ottoman-Safavid rivalry for the next two centuries.

Conquest of the Mamluk Sultanate1517 CE

Syria and Egypt

Selim I defeated the Mamluk Sultanate in two decisive campaigns: at Marj Dabiq (near Aleppo, August 1516), where Mamluk Sultan Qansuh al-Ghawri was killed, and at Ridaniya (near Cairo, January 1517). Egypt, Syria, the Hejaz (including Mecca and Medina), and Jerusalem were annexed. The Sharif of Mecca surrendered the keys of the Holy Cities, and the last Abbasid caliph in Cairo transferred the caliphal title to Selim, making the Ottoman sultan the supreme authority in Sunni Islam. This conquest nearly doubled Ottoman territory and wealth.

First Siege of Vienna1529 CE

Vienna, Austria

Suleyman I besieged Vienna in September-October 1529, reaching the high-water mark of Ottoman expansion into Central Europe. The siege failed due to an early onset of autumn rains (which bogged down the heavy Ottoman artillery), extended supply lines, and determined Habsburg defense. Suleyman withdrew after three weeks without breaching the walls. The failure marked the practical limit of Ottoman overland expansion into Central Europe, though the psychological impact on Europe was immense and drove the formation of defensive coalitions.

Battle of Lepanto1571 CE

Gulf of Patras, Greece

On 7 October 1571, the Holy League (Spain, Venice, Papal States, Genoa, and others) under Don John of Austria destroyed the Ottoman fleet at the Battle of Lepanto in the Gulf of Patras. The Ottomans lost roughly 200 galleys and 30,000 men — the largest naval battle of the 16th century. The victory briefly halted Ottoman Mediterranean expansion and became a celebrated Christian triumph. However, the Ottomans rapidly rebuilt their fleet; they retook Cyprus (already lost during the campaign) and recovered much of their naval capability within a few years, limiting Lepanto's strategic impact.

Second Siege of Vienna1683 CE

Vienna, Austria

Grand Vizier Kara Mustafa Pasha led an Ottoman army of roughly 140,000 to besiege Vienna from July to September 1683. On 12 September 1683, a relief force commanded by Polish King Jan III Sobieski and German Imperial forces broke the siege in the Battle of Vienna — the largest cavalry charge in history. Kara Mustafa was executed by strangulation on the sultan's orders. The defeat triggered the Great Turkish War and the Holy League's systematic counter-offensive that would strip the Ottomans of Hungary, Transylvania, and much of the Balkans by the Treaty of Karlowitz (1699).

Treaty of Karlowitz1699 CE

Sremski Karlovci, Serbia

The Treaty of Karlowitz (26 January 1699), signed between the Ottoman Empire and the Holy League (Austria, Venice, Poland, Russia) after the Great Turkish War, marked the first major Ottoman territorial concessions in Europe. The Ottomans ceded Hungary and Transylvania to Austria, Podolia to Poland, most of Morea (Peloponnese) and Dalmatia to Venice, and acknowledged Azov to Russia. Karlowitz established the precedent that the empire's European territories could be permanently lost and inaugurated the long era of defensive diplomacy.

Auspicious Incident (Vaka-i Hayriye)1826 CE

Istanbul, Turkey

Mahmud II's orchestrated destruction of the Janissary corps in June 1826, which had resisted reform for two centuries and murdered multiple sultans: the Janissaries were slaughtered or exiled and their barracks burned. Mahmud II declared the uprising a rebellion against the state and used loyal artillery units to destroy the Janissary barracks at the At Meydani (Hippodrome). This "Auspicious Incident" (Vaka-i Hayriye) cleared the path for Western-style military and administrative modernization, and its success directly enabled the Tanzimat reforms of the following decades. The Janissaries were replaced by the new Asakir-i Mansure-i Muhammediye (Victorious Soldiers of Muhammad), trained on European models.

Greek War of Independence and Treaty of Adrianople1829 CE

Greece

The Greek War of Independence (1821-1829) was a successful revolt against Ottoman rule backed by Greek nationalist ideology (philhellenism) and the military intervention of Russia, Britain, and France (the Battle of Navarino, 1827, destroyed the Ottoman-Egyptian fleet). The Treaty of Adrianople (1829) and the London Protocol (1830) recognized Greek independence — the first sovereign Balkan nation-state. The war accelerated nationalist movements across the empire and inaugurated the "Eastern Question" that would preoccupy European diplomacy for the rest of the 19th century.

Tanzimat Reforms1839 CE

Istanbul, Turkey

The Tanzimat ("Reorganization") era (1839-1876) was inaugurated by the Gulhane Hatt-i Sherif (Noble Edict of the Rose Chamber, 1839) under Sultan Abdulmecid I, promising equality before the law for all Ottoman subjects regardless of religion. The Reform Edict (Islah Fermani, 1856) extended these guarantees under European pressure after the Crimean War. Reforms included a secular penal code, land registration, new secular schools, a postal service, and a quasi-parliamentary consultative council. The Tanzimat reshaped Ottoman governance on Western lines but also provoked Muslim conservative backlash and accelerated minority nationalism.

Crimean War1853 CE

Crimea and Black Sea region

The Ottoman Empire allied with Britain and France against Russian expansion in the Black Sea region in a war fought from 1853 to 1856. The war began when Russia occupied the Danubian Principalities (Wallachia and Moldavia) and the Ottomans declared war; Britain and France intervened to prevent Russian domination of the Straits and eastern Mediterranean. The conflict demonstrated continued Ottoman geopolitical relevance as a partner of European powers but exposed profound military weakness and fiscal dependence on foreign loans, accelerating European financial penetration through the Ottoman Public Debt Administration (established 1881). Florence Nightingale's pioneering nursing work at Scutari (Uskudar, Istanbul) during this war became a landmark in the history of modern medicine. The war was concluded by the Treaty of Paris (1856), which temporarily checked Russian expansion but imposed further obligations on the Ottomans.

Young Turk Revolution1908 CE

Istanbul, Turkey

In July 1908, the Committee of Union and Progress (CUP, the "Young Turks") — officers and intellectuals inspired by positivism and Ottoman nationalism — staged a revolution, forcing Sultan Abdul Hamid II to restore the 1876 constitution and reconvene parliament. The revolution ended 30 years of autocratic rule and shifted real power to the CUP. Abdul Hamid II was deposed in April 1909 following a counter-coup attempt and replaced by the figurehead Mehmed V. The CUP dominated the empire through the Balkan Wars and World War I, culminating in the Three Pashas' wartime government.

Balkan Wars1913 CE

Balkans

The First Balkan War (October 1912-May 1913) saw a coalition of Bulgaria, Serbia, Greece, and Montenegro seize almost all remaining Ottoman territory in Europe, including Macedonia, Thrace, and Albania. The Second Balkan War (June-August 1913) was fought among the victors over the spoils; the Ottomans retook Edirne. By the Treaty of Bucharest (1913), the empire lost roughly 83% of its European territory and 70% of its European population, retaining only eastern Thrace. The catastrophic losses provoked massive refugee flows and hardened CUP ethnic nationalism.

Mass Deportations of Armenians1915 CE

Eastern Anatolia and Syria

Ottoman authorities ordered mass deportations of Armenian populations from eastern Anatolia beginning in April 1915, resulting in hundreds of thousands of deaths from organized violence, starvation, and disease during forced marches to the Syrian desert. The deportations were ordered by the Committee of Union and Progress (CUP) under the cover of wartime security measures, framing Armenians as a potential fifth column allied with Russia. One of the most consequential and contested events of late Ottoman history, these events are recognized as genocide by many states, parliaments, and historians, though Turkey officially disputes this characterization. The deportations fundamentally altered the demographic composition of Anatolia and shaped 20th-century geopolitics across the region and the broader Armenian diaspora.

Treaty of Sevres1920 CE

Sevres, France

The Treaty of Sevres (10 August 1920) proposed to partition the remaining Ottoman lands among the Allied powers and new states: Greece would gain Smyrna/Izmir and eastern Thrace; Armenia would become independent; France and Britain would receive spheres of influence across Anatolia; the Straits would be internationalized. The treaty was signed by the sultan's government but rejected by Mustafa Kemal's nationalist Grand National Assembly in Ankara. The subsequent Turkish War of Independence (1919-1923) voided Sevres; it was superseded by the Treaty of Lausanne (1923).

Abolition of the Sultanate1922 CE

Ankara, Turkey

On 1 November 1922, the Grand National Assembly of Turkey, led by Mustafa Kemal, voted to abolish the Ottoman sultanate, separating it from the caliphate (which was maintained briefly under a member of the House of Osman until March 1924). Mehmed VI fled Istanbul on a British warship on 17 November 1922. The Turkish Republic was proclaimed on 29 October 1923, and the Treaty of Lausanne (24 July 1923) internationally recognized the new state's boundaries, formally ending the six-century Ottoman era.