After World War I, on 24 December 1918, Fevzi Pasha was appointed to the Chief of the General Staff ("Erkân-ı Harbiye Umûmiye Riyaseti") of the Ottoman Empire. In April 1919, he met with Şevket Turgut Pasha, Cevat Pasha secretly in Constantinople and prepared a report called "Trio Oath" ("Üçler Misâkı") to establish army inspectorate for the defense of homeland. In late April, Fevzi Pasha submitted this report to the Minister of War Şakir Pasha. On 30 April 1919, the War Ministry and Sultan Mehmed VI ratified the decision about the establishing of army inspectorates that had been accepted by the Chief of General Staff On 14 May 1919, he was appointed to the commander of the Inspector of the 1st Army Troops Inspectorate ("Birinci Ordu Kıt'aatı Müfettişi"). On 3 November, he assigned to the task in "Heyet-i Nasîha" and on 31 December, he was appointed to the member of the Military Council ("Askerî Şûra"). He became the Minister of War of Ali Rıza Pasha Cabinet (3 February – 3 March 1920) and Salih Pasha Cabinet (8 March – 2 April 1920).