Economic misery, primarily.
Greece's economy has collapsed since the 2008 financial crisis, and the two EU-IMF bailouts have come with hefty strings attached in the form of austerity measures, ranging from job losses to the sale of public assets. Unemployment is extremely high, with the Hellenic Statistical Authority announcing a jobless rate of 27.4 percent in March. This is highest unemployment rate recorded by a European country in the past three decades. The Labor Institute of the General Confederation of Greek Workers, a labor union research body, this week predicted it would rise to 34 percent by 2016.
Golden Dawn's rise has been as the result of a three-pronged strategy: exploiting anger at the EU, Germany in particular; blaming immigrants for Greece's troubles; and running its own social services including food banks.
In addition, widespread anger at former governing party – the center-left Pasok, which is widely perceived as corrupt – has benefited left- and right-wing parties alike.
The proximate cause, however, was the murder of a 44-year-old man in Athens. In May 2011, Manolis Kantaris was walking his pregnant wife to their car en route to maternity hospital when he was attacked and killed by two men – both Afghan immigrants. The incident fueled violent clashes between immigrants and Greeks, particularly members of Golden Dawn. Golden Dawn's vote increased sevenfold the following year.
Golden Dawn is a product of fear, says Nikos Sotirakopoulos, a Greek research assistant at the University of Kent in Britain, who is currently organizing a series of debates in Athens on his country's precarious political situation.
"The main reason [Golden Dawn grew] was they gave an easily absorbable narrative for the crisis. They said it was the 'Jew bankers' ripping up our country. They also provided services and set-up [paramilitary police] squads in neighborhoods with large immigrant populations, taking old ladies to the ATM and so on," he told The Christian Science Monitor.
Greece is one of Europe's main entry points for immigrants from the Middle East. But Mr. Sotirakopoulos says perceptions of immigrant criminality promoted by Golden Dawn are a pure scare tactic, one that goes along with intentionally targeting immigrants for attack.
"We know they were terrorizing immigrants. Interestingly, in some islands and small towns where there is virtually no immigrant population, and no immigrant crime problem, they had their best results," he said.