Adamantios Olympios Nikolaou (Greek:Αδαμάντιος Ολύμπιος Νικολάου;c. 1790[1] – 19 January 1856), better known asCaptain Diamantis (Greek:Καπετάν Διαμαντής), was a Greekklepht and anarmatolos fromPieria.

Born inRyakia, Diamantis Nikolaou Olympian was the eldest son of the great armatolos and klepht Raideniotis (Ryakiotis) Olympios, best known as Nikolas Kateriniotis Olympios. He operated in the mountains ofVermio, Olympus and Pieria before 1821 and after the outbreak of the Revolution. The interim government and the Supreme Court because of his bravery and military skill appointed him commander ofEvia and Eastern Greece. He successfully confronted the Turks in Evia and in the battle of Faucets. In 1829, as shown in the paroikoi Skopelos records (2 April 1829) he was with his family on the island of Skopelos. In July 1829 he represented Thessalomakedones fighters in theFourth National Assembly at Argos and offers toKapodistrias their proxy. By decision ofKing Otto, he was appointed senator on 16 June 1844 in the Senate body.^[2]

• Revolutionaries from the Ottoman Empire
• 1790s births
• 1856 deaths
• Greek people of the Greek War of Independence
• People from Pieria (regional unit)
• Greeks from the Ottoman Empire

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