Greek PM Alexis Tsipras's path to power

In 1990, a then 16-year-old Alexis Tsipras was being interviewed as one of a number of young Greek activists who had led a revolt against their schools, part of a protest around proposed education reforms.

"We would like it to be our right to decide if, at some point, we want to skip class," Tsipras said, according to the Spanish newspaper El Mundo. 

No surprise then that, nearly 25 years later, Greek's current prime minister is still thumbing his nose at authority, this time against the European powerbrokers who hold the economic fate of his country in their hands.

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It was this message of defiance, of saying enough to the austerity measures imposed on Greece, that helped sweep him and his self-proclaimed radical left-wing coalition into office in January, which led ultimately to the substantial "No" victory in the weekend's referendum

It was a victory to be sure — though muted by the huge financial crunch his country faces.

Within days, Greek banks could be out of cash, unless those same political charms that endeared Tsipras to Greek voters convince his skeptical creditors to part with more financial aid. 

"I'm a compromiser because I want to have realistic goals," Tsipras told the Financial Times in January. "At the same time, I'm very decisive if I know it's necessary to have a fight."

Youngest PM in some time

At age 40, Tsipras is the country's youngest prime minister in over a century and a half. And while he has been a political animal since his teens, joining the youth wing of the Communist Party at age 14, he had a different career path planned, to become an engineer and work in the construction business like his father.

Tsipras was born in Athens to a middle class family, and a father , "who was solidly a man of the centre, voting regularly for the social democratic Panhellenic Socialist Movement (Pasok)," according to the Times.

When he left high school, he also dropped out of the Communist youth, but remained active in student politics at the National Polytechnic University of Athens, according to El Mundo. 

"He was always decisive and a pragmatist, a doer", Andreas Karitzis, a member of Syriza's Central Committee and a fellow student with Tsipras at the Polytechnic, told El Mundo. "He had an uncanny ability to identify achievable goals and do whatever necessary to achieve them."

At the time, Tsipras wanted to study civil engineering and follow in the footsteps of his father who ran a small construction company in Athens, the Times said.

After graduating he did work as a civil engineer in the construction industry, but soon joined the youth chapter of the small leftist party Synaspismos, which eventually morphed into Syriza (also known as the Coalition of the Radical Left). 

He rose up the ranks of Synaspismos, so impressing party officials that in 2006 he was asked to represent the party and the new Syriza coalition as a mayoral candidate for Athens.

Although there was some concerns expressed within the party about his relative youth, he specifically targeted that demographic in the election, boosting the parties fortunes and receiving 11 per cent of the vote, finishing in third place. 

"That was the boom," Dimitris Tzanakopoulos, a Syriza legal adviser, told the Times. "His whole life changed."

A national figure

At that point, Tsipras was a national figure in Greece and two years later would become leader of Syriza, even as his politics are said to have moderated since his Communist youth days. 

Luke March, an expert on radical left and post-Soviet politics at the University of Edinburgh, told Business Insider that Tsipras's "role has been as a leader who is able to present himself as principled but pragmatic, a conciliator and statesmanlike."

It was an image that held when Greeks went to the polls earlier this year and were unswayed by then prime minister Antonis Samaras's  best efforts to portray his opponent as a radical communist.

Tsipras' election ushered in a number of firsts  —  the first time the country would be ruled by a party other than the right-leaning New Democracy or left-of-centre PASOK; the first time an incoming prime minister would not take a religious oath (Tsipras is an avowed athiest). And it was the first time Greece elected an unmarried prime minister.

Tsipras has been with his high-school sweetheart Peristera 'Betty' Batziana for two decades. The couple has two sons, (one of whom, Orpheus Ernesto, is named after the Cuban guerilla fighter Ernesto "Che" Guevera) and for years had been living in a rented apartment in Athens.

He may have also been the first prime minister, at least in recent times, to not wear a necktie during the oath of office.

For Tsipras, it is a casual style that voters are familiar with. And one he plans to continue, he has joked, until the country gets some debt relief,  meaning his neck could be bare for the foreseeable future.