Following the attrition battle on the Sakarya River (Battle of Sakarya) in August–September 1921, the Greek Army of Asia Minor under General Anastasios Papoulas retreated to a defensive line extending from the town of İzmit (ancient Nicomedia) to the towns of Eskişehir and Kara Hisâr-ı Sahib (present-day Afyonkarahisar).

The Greek line formed a 700 km arc stretching in a north–south direction along difficult hilly ground with high hills, called tepes, rising out of broken terrain and was considered to be easily defensible.

The morale of the Greek troops was low, as many had already been under arms for several years, and there was no prospect for a quick resolution of the war.

Despite pressure to attack building up at Ankara, Mustafa Kemal who had been appointed Commander-in-Chief of the TBMM government, waited and utilized the breathing space to strengthen his forces and split the Allies through adroit diplomatic moves, ensuring that French and Italian sympathies lay with the Turks rather than the Greeks.

The Greek forces were organized in the "Army of Asia Minor", under Lieutenant General Georgios Hatzianestis, with a total of 220,000 men in 12 infantry and 1 cavalry division.

It also included an independent Cavalry division and smaller regiment-sized Military Commands, mainly for interior protection and anti-guerrilla operations.

Although numerically strong, the Greeks were very deficient on heavy artillery (only 40 outdated pieces existed in the entire front) and cavalry (one half-company per division).

The Turkish forces were organized in the Western Front, under Mustafa Kemal Pasha, with a total of 208,000 men in 18 infantry and five cavalry divisions.

For the purposes of the offensive, the Western Front HQ was located on Koca Tepe hill, some 15 km south of Kara Hisâr, very close to the battle lines.

In a second phase the 1st and 2nd Armies would meet in the area south of Kütahya, closing a ring around the Greek forces in Kara Hisâr and completely encircling them.

The Greek high command had anticipated a major Turkish offensive, it was however uncertain of the exact direction it would come.

Unknown to them at the time, the railroad from Ankara, that the Greeks destroyed in summer 1921 during the withdrawal after the battle of Sakarya, was still not restored and was not operational.

The gorge was guarded by a patrolling Greek rifle company, which was easily overrun by the advancing Turkish cavalry.

The arrival as a reinforcement of the II Corps' 7th division in the afternoon prompted a Greek counterattack which was able to only partially restore the line.

In its order at 23:00 hours on 26 August to the I and II Corps the Army expressed the opinion that the Turks had still not revealed the main axis of their offensive.

Due to the broken communications, the Army HQ in Smyrna didn't receive the notifications of the I and II Corps and had the impression that things developed as it had ordered.

At 10:30 hours the Greek Ι Corps issued an order of general withdrawal some 20 km to the north of its original line, and the subsequent evacuation of Kara Hisâr.

The order was not received by the Greek 1st division, whose telephone contact with the Ι Corps had been cut and couldn't establish wireless communication, and remained in position.

Unaware of the absence of Frangou Group's units, the Greek 4th division's exposed column was attacked at 07:00 and taken by surprise, and subsequently broken.

After repeated failed efforts to establish wireless communication with the Greek I Corps Frangou ordered his units to begin their withdrawal to Dumlupınar position at 16:00 hours.

At 05:00 hours on 29 August all units of Frangou Group had reached the positions around Dumlupınar, in good order despite the pressure of the Turkish IV corps.

During the night of 28–29 August the Turkish VI Corps (of the Second Army) had advanced to the west and reached the north of Trikoupis Group.

Quickly the Greek 9th division found itself attacking against superior Turkish forces (the 4th Corps) and fell into defense.

The Turkish forces had similarly been unable to destroy the Trikoupis Group, despite having encircled it with their II, IV, V and VI Corps.

At 23:00 on 29 August, the badly battered Greek units of Trikoupis Group, disengaged and began marching towards Çalköy (38°55′47.7″N 30°04′6.7″E / 38.929917°N 30.068528°E / 38.929917; 30.068528), which was thought to be weakly held by Turkish forces.

Trikoupis made a council with the commanders of his divisions, who proposed that the Group continue its westward march through Alıören (38°56′47.0″N 29°59′57.3″E / 38.946389°N 29.999250°E / 38.946389; 29.999250) to Banaz.

After receiving the reports from his subordinate units Trikoupis, realising that his forces were insufficient to withstand a Turkish attack, changed his mind and ordered continuation of the march to Alıören and then Banaz.

Even though the road to Alıören was open, Trikoupis had lost invaluable time before ordering the continuation of the march to the west.

By 16:00 hours, the Turkish artillery became particularly effective, inflicting heavy casualties to the densely concentrated Greek forces.

A column of 2,000 men (mainly from the Greek 12th division) surrendered at 20:00 hours on 1 September to Turkish cavalry units.