Born on the island of Zakynthos, he was a fighter in the Revolution of 1821 and was later better remembered as a historian, politician, poet, writer, judge and philosopher.
He completed his schooling in Zakynthos, together with Panos Kolokotronis, son of Theodoros, a circumstance which would prove poignant in both Tertestis’ and Theodoros’ lives many years later.
Following this, he left for Italy to further his studies, but at the outbreak of the 1821 Revolution he hurried back to the Peloponnese to join in the fighting, where he fell ill and retreated to the island of Kalamos.
Back in Zakynthos he was acquainted with and became friends with Dionysios Solomos, Greece’s national poet, famous for writing the future Greek National Anthem.
He would return to the front line to fight, but also spent more of his time as a tutor and teacher, particularly to the children of the fighters.
Following the Revolution, he was appointed as Professor for General and Greek History in Nafplio and in 1833 Tertsetis became a judge.
In 1834, he was member of the panel of judges in the capital Nafplio, presiding over the bogus charges brought on by the foreign Monarch of Greece Otto, to have 2 heroes of the Greek Revolution, Theodoros Kolokotronis and Dimitris Plapoutas charged with treason and sentenced to be executed.
Georgios Tertsetis and fellow judge Anastasios Polyzoidis refused to sign the document condemning the two men, who were later acquitted and pardoned in 1835.
Tertsetis later represented Zakynthos in Parliament and also wrote a biography on Theodoros Kolokotronis, based on his memoirs.