After First World War, Prime Minister Venizelos lobbied hard at the 1918 Paris peace conference, urgently presenting his views for an expanded Hellas, especially to include the large Greek communities in Northern Epirus, Thrace and Minor Asia, and even more compelling was the real need to protect the Greeks who were subjected to harsh treatment by Neoturks, during World War I. This conflicted with colonial designs of Italy to take possession of a large part of southwestern Anatolia, which has been confirmed by the allies in two separate formal treaties in 1915 and 1917 and they landed troops in Antalya marching them toward Smyrna. An alarmed Venizelos appealed to Lloyd George.

The British Prime Minister favored the occupation of the Smyrna area by Greek forces to protect the large Greek population there. On May 15, 1919 Greek army landed peacefully on Asia Minor, for the first time since byzantine times 500 years earlier. Venizelos appointed Stergiades as governor of Smyrne, and he kept the order in the city of Smyrne, treating musulmans and christians in a fair way. Meantime turkish irregular forcse (tsetes) harasshed the greek army and pillaged greek cities. In June, 20 they massacred 2500 civilians in the city of Aidinion. July 29, Leonidas Paraskeuopoulos became general of the Army and came in Smyrne to assume his duties. The events also awakened a new sense of patriotism in a Turkish population depressed by decades of national weakening. At this time a new personality had emerged, that of General Mustapha Kemal. Kemal formalized his movement into a national congress in February 1920 in a declaration of independence from the government in Constantinople. He established the new capital in the center of the country at Ankara and vowed never to allow Turkey to be partitioned or controlled by the various European interests.

During one year, nothing changed in Minor Asia. This delay of the allies to arrange the peace terms with Turkey following the end of World War I was disastrous for Greece. Not only did the Kemalist government become stronger, but the allies foresaw a prolonged and costly new war in Asia Minor. By mid-June 1920 a Turkish nationalist attack on the British position near Nicomedia at the eastern end of the sea of Marmara gave Greece the chance to demonstrate her military effectiveness. The troops advanced east from the agreed-upon holding line, and occupied an area from Prussa to Philadelfeia and Panormos. Philadelfeia was the last greek city that was occupied by Turks in 14th century. Greek army also liberated Eastern Thrace - Adrianople, Alexandroupolis, Raedestos, Heraclea - and came closer to the old capital of Medieval Hellenism, Constantinople, which allied forces insisted to remain under turkish possession. Colonel Tzafer Tayiar was captured as prisoner. In this optimistic atmosphere the treaty of Sevres was finally signed on August 10, 1920. According to the treaty, Hellas possesed Eastern Thrace and Smyrne while Armenia, Syria, Palestine became independent states, Kurdistan became autonomous, and Cyprus was a british colony.

After King Alexander died leaving no heirs, the general elections scheduled to be held on November 1, 1920 suddenly became the focus of a new conflict between the supporters of Venizelos and those of King Constantine. The war-weary Greek people opted for change. To the surprise of many, Venizelos won only 118 out of the total 369 seats. The crushing defeat obliged Venizelos and a number of his closest supporters to leave the country. Those elections were a terrible mistake that Venizelos made, because at that time he was the only capable politician to handle the difficult situation.

The new government prepared for a plebiscite on the return of King Constantine. Remembering his pro-German posture during the war, the allies warned the Greek government that if he should be returned to the throne they would cut off all aid to Greece. The French and the Italians took the opportunity to conclude private agreements with the Kemalists in recognition of their mounting strength. Lenin also supported Kemal with money and ammunition. Also the new government, under Gounares, replaced all the veteran officers and the leadership of the army was given to Anastasios Papoulas.

Kemal did not accept the Sevres Treaty and continued the war. So the only option for Greeks was to force Turks to accept the Sevres agreement in the battlefield. Earlier in December, 1920 the Greeks had advanced to Eski Shehir. Finding stiff resistance they retired to their former positions. In March 1921 the advance was more in earnest, but so was the defense by the entrenched Turkish Nationalists, who were better prepared and equipped like a regular army.

Not willing to go backwards, the Greek government decided to go forward against Kemal and Ankara. King Constantine arrived in Smyrna in early June 1921. The Greek army again advanced on 1st July Anamorion (Afyon Karahisar), on 4th July Koutaheia, on 6th July Doruleaon (Eski Shehir). The principal objective was Ankara and the Greeks convinced themselves that if they could capture this nationalist capital, they would destroy the Turkish resistance and victory would be theirs. On August 14, 1921, the Greek assault began. In an all-out effort they managed to reach the Sakaraya River and the city of Gordion where Greater Alexander had cut the "Gordion Desmus", about 40 miles from Ankara. The casualties on both sides were enormous, but Greeks managed to win also the battle of Cale-Groto.