A distinguished soldier known for his personal bravery, he became famous as "The Black Rider" during the Greco-Turkish War of 1919–1922, where he commanded the 5/42 Evzone Regiment.

After the Greek defeat in the war, along with other Venizelist officers he launched the 11 September 1922 Revolution that deposed 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.

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.

He entered the NCO School in 1910 and, after being assigned to the rank 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.

After the change in power in Greece (November 1920) and the return of king Constantine, he was the only officer, who had participated in the National Defence movement, who was not dismissed from the army.

During the Greco-Turkish War of 1919-1922, the Turks called Plastiras Kara Biber ("The Black Pepper"), while the 5/42 Regiment of Evzones became known as the Şeytanın Askerleri ("Satan's Army").

The Army's resentment at the political leadership in Athens resulted in the outbreak of the 11 September 1922 Revolution, led by Plastiras, Colonel Stylianos Gonatas and Commander Phokas.

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, 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.

Plastiras formed a coalition government with Sofoklis Venizelos' Liberals, and attempted to address the great problems of the country.