|Battle of Kütahya–Eskişehir|
|Part of Greco-Turkish War (1919–1922)|
Greek cavalry attack
|Grand National Assembly||Greece|
|Commanders and leaders|
|İsmet İnönü||Anastasios Papoulas|
55,000 men[Note 1]
711 light and heavy machine guns
~110,000 men 
106,000 men (11 divisions, 1 cavalry brigade)
908 light and heavy machine guns
|Casualties and losses|
30,809 soldiers deserted
18 cannons, 47 heavy and 34 light machine guns lost
The Battle of Kütahya–Eskişehir (Greek: Μάχες Κιουτάχειας-Εσκί Σεχίρ (Δορυλαίου), Turkish: Kütahya-Eskişehir Muharebeleri), was fought between July 10 and July 24 (or June 27 and July 10 in the old calendar, then in use in Greece), 1921 when the Greek Army of Asia Minor defeated the Turkish troops commanded by İsmet Pasha in defence of the line of Kara Hisâr-ı Sahib (present day Afyonkarahisar)-Kütahya-Eskişehir. It was also known in some Greek historiography as the Battle of Dorylaion and known in Turkish historiography as the Battles of Kütahya-Eskişehir (Turkish: Kütahya-Eskişehir Muharebeleri or Kütahya-Eskişehir Savaşları). It was part of the Greek Asia Minor Campaign and the Turkish War of Independence of 1919–1922.
Strategically, the battle was of little importance as the Greeks failed to grasp the opportunity to encircle the retreating Turkish troops. This proved later to be a major strategic error, when the two sides had to meet each other again during the much more fierce Battle of Sakarya which turned the tide in favour of the Turks.
The Greek Army managed to break through Turkish resistance and occupied the towns of Kara Hisâr-ı Sahib, Kütahya and Eskişehir, together with their inter-connecting rail-lines.
The Turks despite their defeat managed to avoid encirclement and made a strategic retreat on the east of Sakarya river. On August 5, 1921 İsmet İnönü was replaced by Birinci Ferik Fevzi Çakmak as the Minister of the General Staff (Erkân-ı Harbiye-i Umumiye Reis Vekili) of the Ankara government after his failure to check the Greek offensive.
This was the major decision point that sealed the Greek destiny in Anatolia. The state and Army leadership, including King Constantine, Prime Minister Dimitrios Gounaris, and General Anastasios Papoulas, met at Kütahya where they debated the future of the campaign. The Greeks with rejuvenated their faltering morale failed to appraise rationally the strategic situation that favoured the defending side; instead, in the overall climate of enthusiasm, the leadership was polarised into the risky decision to pursue an engagement with the Turks on their last line of defence, close to Ankara. Only few voices supported a defensive stance, but they were not heard.
After a delay of almost a month, that gave adequate time to the Turks to organise their defences, 7 of the Greek divisions crossed east of Sakarya River.
- Επίτομος Ιστορία Εκστρατειας Μικράς Ασίας 1919–1922, Εκδόσεις Διευθύνσεως Ιστορίας Στρατού, Αθήναι 1967, page 145 (in Greek)
- Turgut Özakman: Şu Çılgın Türkler, August 2005, Bilgi publishing house, 52. Edition, ISBN 975-22-0127-X, page 705 (footnote 1). (in Turkish)
- Türk Kurtuluş Savaşında İsmet İnönü (Hazırlayan: Genelkurmay Askeri Tarih ve Stratejik Etüt (ATASE) Başkanlığı), İnönü Foundation. (in Turkish)
- Επίτομος Ιστορία Εκστρατειας Μικράς Ασίας 1919–1922, Εκδόσεις Διευθύνσεως Ιστορίας Στρατού, Αθήναι 1967, page 153: 2,526 officers, 107,476 soldiers (in Greek)
- Tarih İçinde Polatlı Archived September 17, 2011, at the Wayback Machine., Ankara Polatlı Belediyesi (Ankara Polatlı Municipality), page 111 (Pdf page 7)
- Επίτομος Ιστορία Εκστρατειας Μικράς Ασίας 1919–1922, Εκδόσεις Διευθύνσεως Ιστορίας Στρατού, Αθήναι 1967, page 204 (in Greek)