Key Facts
- Founded
- 1832, by Treaty of Constantinople
- Duration
- 1832–1924 and 1935–1973
- Governing ideology
- Megali Idea (territorial unification of Greeks)
- Constitutional change
- Absolute to constitutional monarchy, 1843
- Final abolition
- 1973 under Regime of the Colonels
Imperial Zenith Metrics
Historical Trajectory
Phase I: Rise
Greece emerged as an independent kingdom in 1832 following the Greek War of Independence against the Ottoman Empire, formally recognised by the Treaty of Constantinople. The new state, initially ruled absolutely by King Otto, transitioned to a constitutional monarchy after the 1843 revolution. Early territorial expansion included the annexation of the Ionian Islands in 1864 and Thessaly in 1881, driven by the Megali Idea of uniting Greek-populated lands under one state.
Phase II: Zenith
Under Eleftherios Venizelos following the 1909 Goudi coup, Greece achieved its greatest expansion. Victory in the Balkan Wars of 1912–1913 nearly doubled the country's territory and population. Greece subsequently entered World War I on the Allied side, gained further territory at the Paris Peace Conference, and launched the Asia Minor Campaign against the Ottomans, representing the high-water mark of Greek territorial ambition and military power.
Phase III: Decline
Greece's catastrophic defeat in the Greco-Turkish War of 1919–1922 ended Megali Idea aspirations, triggering revolution, the abdication of Constantine I, and the Treaty of Lausanne's compulsory population exchange. The monarchy was abolished in 1924, restored by a disputed referendum in 1935, interrupted by Axis occupation in World War II, and finally abolished in 1973 by the military junta, confirmed by a free referendum in 1974 that established the Third Hellenic Republic.
Notable Imperial Reigns
Selected rulers mapping the empire’s trajectory