Leonardopoulos-Gargalidis coup d'état attempt

The Leonardopoulos–Gargalidis coup attempt (Greek: Κίνημα Λεοναρδόπουλου-Γαργαλίδη) was a failed military coup launched on 22 October 1923 in Greece by pro-royalist military officers under the Lieutenant Generals Georgios Leonardopoulos and Panagiotis Gargalidis, and the Colonel Georgios Ziras. Its failure discredited the monarchy and contributed decisively to the establishment of the Second Hellenic Republic in March 1924.

Following the Greek defeat in the Asia Minor Campaign against Turkey, the Greek Army, led by Venizelist Colonels Nikolaos Plastiras and Stylianos Gonatas, overthrew the royalist government in September 1922 and forced King Constantine I into renewed exile. His eldest son, George II succeeded him, but the position of the monarchy remained precarious. The military-led "Revolutionary Government" tried and convicted six leading royalists to death as scapegoats for the country's military defeat, and gradually steered the country in the direction of a republic. On 18 October 1923, the Revolutionary Government proclaimed elections to be held on 16 December for a National Assembly which would decide on the country's future form of government. The Revolutionary Government however, headed by Gonatas, had passed an electoral law which heavily favoured the Venizelist Liberal Party and the other anti-monarchist parties.

The prospect of the elections and an almost-certain regime change led to the creation of a heterogeneous coalition in the ranks of the army, which aimed to overthrow the government. Its main driving force was the so-called "Majors' Organization" (Οργάνωση Ταγματαρχών) of royalist middle-ranking officers, which was in close contact with the royalist former Deputy Chief of the Army General Staff and future dictator, General Ioannis Metaxas, but several disgruntled Venizelists, most prominently Leonardopoulos and Gargalidis, also joined. The conspirators managed to win over the bulk of the military units in northern Greece and the Peloponnese, but failed to make inroads in the garrisons of Athens, Thessaloniki or the other major cities, as well as in the overwhelmingly Venizelist Navy.

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