Nikolaos Plastiras (Greek: Νικόλαος Πλαστήρας) (November 4, 1883 - July 26, 1953) was a Greek general and politician, who served thrice as Prime Minister of Greece. A distinguished soldier and known for his personal bravery, he was known as "O Mavros Kavalaris" ("The Black Rider") during the Greco - Turkish War of 1919 - 1922. After the Greek defeat in the war, along with other Venizelist officers he staged a coup against King Constantine I of Greece and his government. The military led government ruled until January 1924, when power was handed over to an elected National Assembly, which later declared the Second Hellenic Republic. In the interwar period, Plastiras remained a devoted Venizelist and republican. Trying to avert the rise of the royalist People's Party and the restoration of the monarchy, he led two coup attempts in 1933 and 1935, both of which failed, forcing him to exile in France.

During the Axis Occupation of Greece in the Second World War he was the nominal leader of the EDES resistance group, although he remained in exile in Marseilles. After the occupation, he returned to Greece and served as a centrist Prime Minister three times, often in coalition with the Liberal Party. In his last two governments, he tried to heal the rift caused in Greek society by the Greek Civil War, but was unsuccessful.

He was born in 1883, in Karditsa, Greece. Plastiras' parents were originally from Morfovouni (formerly Vounesi), a village in the Agrafa mountains of southwestern Thessaly. The municipality was renamed for General Plastiras and Morfovouni is the present capital of Plastiras Municipality. The family moved to Karditsa before Plastiras was born.

After finishing school in Karditsa, he joined the 5th Infantry Regiment as a volunteer in 1904. He fought in the Macedonian Struggle, and participated in the military coup of 1909. He entered the NCO School in 1910 and, after being assigned to the rank of 2nd Lieutenant in 1912, he fought with distinction in the Balkan Wars, where he earned his nickname "The Black Rider". He first rose to wider prominence when, as a Major, he supported the Movement of National Defence of Eleftherios Venizelos during the First World War. He fought with distinction with the 5/42 Evzone Regiment at the battle of Skra - di - Legen and was promoted to Lieutenant Colonel. In 1919, Colonel Plastiras commanded the 5/42 Evzone Regiment in the Ukraine, as part of an Allied force aiding the White Army in their ultimately unsuccessful fight against the Red Army. His force was then transferred to Smyrna in Asia Minor via Romania.

During the botched war with Turkey from 1919 – 1922, the Turks called Plastiras Kara Biber ("The Black Pepper"), while the 5/42 Evzones became known as the Şeytan Asker ("Satan's Army"). His advance was finally halted at Kale - Grotso, just across the Sakarya River. Soon after, at the battle of Sakarya, the Greeks were forced to begin their retreat. After the Turkish breakthrough in August 1922, Colonel Plastiras' unit was among the few retaining any coherence, withdrawing orderly to the coast, fighting off superior Turkish forces, rallying around him men from other units and saving several thousands of Anatolian Greeks along the way. For these feats he earned immense popularity, especially among the Ionian Greeks he helped save. The remnants of the Greek Army made their way to the islands of the Eastern Aegean, where the Army's resentment at the political leadership in Athens resulted in the outbreak of the 1922 Revolution on September 11, led by Plastiras, Colonel Stylianos Gonatas and Commander Phokas.

Having the support of the Army and much of the people, the Revolution quickly assumed control of the country. Plastiras forced King Constantine to resign, called upon the exiled Venizelos to lead the negotiations with Turkey which culminated in the Treaty of Lausanne, and set about to reorganize the Army to protect the Evros line against any Turkish advance into Western Thrace. One of the most controversial acts of the revolutionary government was the trial and execution of five royalist politicians, including former PM Dimitrios Gounaris and the former Commander - in - Chief, General Georgios Hatzianestis, on November 28, 1922 as those mainly responsible for the Asia Minor Disaster, in the infamous "Trial of the Six".

Plastiras faced multiple challenges in governing Greece. The 1.3 million refugees from the population exchange had to be catered for in a country with a ruined economy, internationally isolated and internally divided. The Corfu incident, and a botched Royalist coup in October 1923 were evidence of this. After the failed royalist coup, King George II was forced to leave the country. Nonetheless, he managed to restore some order to the state and to lay the groundwork for the Second Hellenic Republic. After the elections of December 1923 for the new National Assembly, he resigned from the Army on January 2, 1924, retiring to private life. In recognition of his services to the country, the National Assembly declared him "worthy of the fatherland" and conferred to him the rank of Lieutenant General in retirement.

Plastiras was even admired by his greatest enemy, Mustafa Kemal (Atatürk). At the end of the war, during the negotiations that took place regarding the exchange of populations between Greece and the newly formed Republic of Turkey, Atatürk is quoted telling Plastiras, "I gave gold and you gave me copper."

The Republic that he had helped found proved an unstable one. Coups, counter coups, the conflict between Venizelists / Republicans and Royalists, and constant economic problems plagued Greece. Plastiras, persecuted during the Pangalos dictatorship, attempted to lead a coup in March 1933, after the anti - Venizelists won the elections, but facing universal reaction (even from Venizelos himself), he was forced to flee abroad. Finally, after the failed Venizelist revolt of 1935, although still abroad, he was condemned in absentia to death. Nonetheless he maintained a high prestige as a war hero and because of his integrity and staunch Republicanism. From his French exile, he watched the Germans overrun Greece, and played a role in the creation of the EDES resistance group, whose titular leadership he had.

He returned to Greece in 1945, after his selection as prime minister following the December events of 1944, primarily because he was a commonly accepted personality. Plastiras attempted to tread a middle path between the British, who were supporting the returned government - in - exile and the return of King George II, and the democratic - leftist guerilla of the EAM / ELAS. During his premiership, the Varkiza Agreement was signed. His moderate policies and republican sympathies earned the distrust of the British, and he was dismissed after only three months in office.

In 1949, after the end of the Greek Civil War, Plastiras founded a new party, the National Progressive Centre Union (Εθνική Προοδευτική Ένωση Κέντρου, EPEK), forming a following of disappointed Liberals and left leaning democrats. He preached a message of national reconciliation, which put him in conflict with the conservative establishment which sought to punish those who had fought to establish a communist government. Together with Sofoklis Venizelos and George Papandreou, Plastiras formed a coalition government in 1950, which fell, however, when his partners retired. In the September 1951 elections, EPEK emerged as the strongest of the centrist parties. Plastiras formed a coalition government with Sofoklis Venizelos' Liberals, and attempted to address the great problems of the country. His government initiated the economic recovery and the reconstruction of Greece. A monument to this is the construction of the dam at the Tavropos (Megdovas) River to form a lake, a program that he initiated. The lake and dam, both formerly named Tavropos, now bear his name. His policy of conciliation, however, was bitterly assailed from the right, distrusted from the left, and undermined even by members of his own cabinet. A defining moment of his failure was the conviction and execution of Nikos Belogiannis in March 1952. After losing the elections of November 1952, his political career, and with it the liberal 'Centrist Intermission', came to an end. He died in poverty in 1953 in Athens.