[1] He fought in the Balkan Wars of 1912–13 in the ranks of the 7th Infantry Regiment, fighting in the battles of Sarantaporo and Bizani, and the capture of Florina.
[3] In 1917–18 he fought in the Macedonian front of World War I, as well as in the Allied intervention in Ukraine in 1919, as a battalion commander in the 7th Regiment.
[1][3] During the Asia Minor Campaign he was a lieutenant colonel and served as chief of staff of the Smyrna Division until October 1920,[3] as well as commanding the 4th, 7th and 14th Infantry Regiments and he particularly distinguished himself during the Greek retreat in August 1922, where he managed to lead his column to safety from Ali Veran to Takmak.
[2] He commanded the TSKM, composed of the 12th and 20th divisions, from 6 March to 8 April 1941, when he was replaced by Major General Christos Karassos.
[5] During his career, Ioannis Kotoulas published a number of works on military history, including studies on Xenophon and the Ten Thousand (1929), infantry combat, the Catalan Company in 14th-century Greece, Thessaly in the Trojan War, etc.