He was appointed as National Defence Minister and Deputy Prime Minister by Mustafa Kemal Paşa in 1920, commanding numerous military successes throughout the Turkish War of Independence, notably during the Battle of Sakarya. He succeeded Mustafa Kemal as Prime Minister in 1921, resigning in 1922 to engage in the successful Battle of Dumlupınar. He was appointed Field Marshal (Mareşal) in 1922 at the recommendation of Mustafa Kemal. He had succeeded İsmet İnönü as the Chief of General Staff in August 1921 and continued serving after the Turkish Republic was declared in 1923. Adopting the surname 'Çakmak', he was a candidate to succeed Mustafa Kemal Atatürk as the President of Turkey after Atatürk's death in 1938, but stood down in favour of İnönü. He continued to serve as Chief of General Staff until 1944, after which he became a Member of Parliament for Istanbul from the Democrat Party. He later resigned from the Democrats and co-founded the Nation Party headed by Osman Bölükbaşı.