Stylianos Gonatas (Greek: Στυλιανός Γονατάς; 15 August 1876, Patras – 29 March 1966, Athens) was a Greek military officer and Venizelist politician and Prime Minister of Greece between 1922 and 1924.
Gonatas was born in Patras. He entered the Military Academy in 1892 and graduated in 1897. As a Lieutenant, he participated in the Macedonian Struggle (1907–1909), and became aide-de-camp to Colonel Nikolaos Zorbas immediately following the 1909 Goudi Revolt. He also participated in the 1912-13 Balkan Wars and in the Allied Expedition to the Ukraine in 1919. Subsequently, he took part in the Asia Minor Campaign with the rank of Colonel, first as a staff officer and later as divisional commander.
In August 1922, the Greek Army suffered a catastrophic defeat at the hands of the Turks, which forced it to evacuate Anatolia in great haste. In Greece, this disaster led to a political crisis, and military revolts broke out in September amongst the evacuated troops in Thessaloniki, Chios and Lesbos, headed primarily by Venizelist officers.
The army contingents in Lesbos formed a Revolutionary Committee headed by Colonel Gonatas, which dispatched by airplane the following demands to Athens: the dismissal of the government, the dissolution of Parliament, the holding of new elections, and the abdication of King Constantine in favour of the Diadoch, Prince George. The revolutionary movement swiftly spread to other centres of old and new Greece, aided by the Fleet, which had joined their cause. The cabinet immediately resigned, and on September 27 King Constantine abdicated for the second time in the course of his career, and the Diadoch succeeded to the throne of Greece as King George II.