Born in Naupactus, he obtained his law degree from the University of Athens. He was first elected to the Greek Parliament in 1926 representing his native prefecture of Aetolia-Acarnania, and was repeatedly elected to office until 1964.
In 1961, however, he was one of many conservatives who joined the Center Union (EK), in opposition to the corruption of right-wing governments at the time. In 1964, after EK came into power, he became Speaker of the Greek Parliament.
On July 15, 1965 he was appointed Prime Minister of Greece by king Constantine, after the latter dismissed George Papandreou, Sr., a move that is known as Apostasia of 1965. He was followed by many EK conservatives and with support from conservative National Radical Union MPs tried to form a government, but failed to get past a vote of confidence in parliament. He was replaced on August 20 of the same year.
Athanasiadis-Novas also wrote some poetry and prose under the pen name Georgios Athanas (Γεώργιος Αθάνας). Literary critics found very little in the way of value in his works, but he found some popularity among his detractors, who used them to ridicule his less-than-distinguished political career. The stanza:
- Itan ta stithia sou
- aspra san galata
- kai mou 'leges:
- gargala ta
- Your breasts were
- White as milk
- And you urged me
- "Tickle them!"
gained him the comical nickname "Gargalatas", Tickler. Only after 40 years has it been proven that the fact that he wrote this stanza was an urban legend. It all started from an article of Costas Stamatiou at the newspaper Ta Nea, with the intention to ridicule him. Lefteris Papadopoulos cleared up the situation with an article at the same newspaper in 2004.
He died in Athens in 1987, aged 94.
| Prime Minister of Greece