In 1844, during the debate for the promulgation of the Greek constitution, Prime Minister Ioannis Kolettis, who had played a significant role in Greek independence, coined the phrase “Megali Idea” (Great Idea), which envisaged the restoration of the Orthodox Christian Byzantine Empire, under the leadership of the Greeks. This restored kingdom would occupy the lands that the Byzantine Empire occupied at its zenith. Constantinople would be its capital.
Since the fall of Constantinople in 1453, the Greek thinkers remained hopeful that the Byzantine Empire would be restored some day. During the eight-year Greek war of independence from Ottoman rule (1821 to 1828), the Megali Idea was a major inspiration. The slogan, “Once more, as years and time go by, once more they shall be ours,” was popular among the Greek revolutionaries, who believed that once Greece became independent, their national priority would be to use their national resources to restore the former Byzantine Empire.
In the first Balkan war of the twentieth century, the Greeks, in league with three other Orthodox Kingdoms of the region, Bulgaria, Serbia, and Montenegro, came close to occupying Constantinople. The four kingdoms were former colonies of the Ottoman Empire. They formed the Balkan League and declared war on their former colonial master on October 8, 1912.
The Ottoman elite could not believe that they were being attacked by their former vassal states. They thought that they would easily destroy the Balkan League and reestablish their colonial power over them. But there was an unexpected outcome in the military engagement that followed. Within ten days of the conflict, the Ottoman army began to collapse. The Balkan League managed to kill 35,000 soldiers, a third of the army that the Ottomans had put on the ground, and they made deep incursions inside Ottoman territory.
The Greeks managed to capture important ports and they sank several Ottoman warships, which meant that the Ottomans had no means of transferring their army from Libya to the Balkans. The fortress city of Edirne was besieged by the Bulgarian forces and they were just 25 miles from Constantinople. By January 1913, the Ottomans had lost 83 percent of their European territory and 70 percent of their European population. The shocking defeat of the Ottoman Army by its former colonies caused chaos in Constantinople. There were protests against the government for mismanaging the Balkan conflict and causing a great humiliation to the Sultan and the Empire.
On January 23, 1913, there was a Young Turk coup led by Enver Pasha in Constantinople. The Minister for War was killed for his mismanagement of the Balkan War which led to the Ottoman defeat, and the government of Grand Vizier Kâmil Pasha was overthrown. The power in the Ottoman Empire passed into the hands of the military hardliners of the Committee of Union and Progress (CUP).
The Balkan League could not make further progress inside the Ottoman Empire because differences emerged among them regarding the sharing of the spoils, particularly Macedonian territory. Bulgaria took its attention away from the Ottoman Empire and attacked its former allies, Greece and Serbia on 16 June 1913. This was the Second Balkan War. Romania, which had its own grievances against Bulgaria, joined the war on the side of Greece and Serbia.
Bulgaria was decisively defeated in the Second Balkan War which lasted for six weeks (June 29 to August 10, 1913). But this war gave the Ottoman Empire, now under the CUP, the opportunity to take back some of the territory that it had lost in the First Balkan War. Thrace and Edirne went back to the Ottomans. The Treaty of Constantinople brought the Second Balkan War to an end. But neither side was happy with the territories that it had and new wars were inevitable.
During the First World War that followed, there were large-scale genocides against the Greeks (and the Armenians) in Asia Minor and several other parts of the Ottoman Empire. By the end of the war, more than million Greeks had fled from the Ottoman lands to Greece and other places in Europe.
In May 1919, the Greek army landed in Smyrna, and the Greco-Turkish War of 1919-1922 began. The Greeks quickly took control of the western and northwestern part of Anatolia, including a number of major cities. It seemed that they were on the verge of conquering all of Anatolia. But in 1921, the Soviet Union entered the war on the side of the Ottomans, and the Greeks were forced to retreat. There is some evidence to show that the French too were assisting the Ottomans. In August 1922, the Greeks and the civilian population in Smyrna had to flee in whatever boats they could find. The city of Smyrna was burned to ashes by the Ottoman forces.
The Megali idea of restoring the Byzantine Empire was weakened considerably but it did not die with the debacle in the war of 1919 to 1922. The idea is still alive. It continues to inspire some political movements in Greece, though it is no longer a driving force behind Greek foreign policy.