As economies falter, established political parties feel the heat from leftwing and far right groups

From the anti-austerity firebrands of Greece's imminent elections to the corruption crusaders in Prague, from the Pirates of Berlin to the populists who scored well in France's presidential election, a new wave of anti-establishment parties are on the rise across Europe, posing a threat to the political elite.

Their causes vary – some are from the left, some from the right. But in many cases austerity is their bete noire, and this week governments in Netherlands and Romania were toppled because of opposition to programmes of budget cuts. They may not be the last.

Greece

Greece, the country that triggered Europe's debt crisis, is gearing up for a general election that is likely to see extremist parties win seats on a wave of anti-austerity sentiment.

With barely a week before Greeks cast their ballots, analysts are describing the May 6th poll as "the most unpredictable" in recent history. The only certainty, they say, is that the vote will result in a hung parliament with as many as ten parties entering the 300-seat House – an outcome likely to engulf the crisis-hit nation in debilitating political instability.

"This is the most open election since the restoration of democracy in 1974. Anything is possible," said Takis Theodorikakos who heads the GPO polling group. "For the first time ever we have a huge number of undecided voters with around 30% unsure how they will cast ballots. Eight out of 10 say they will decide in the last three days and it is they who will determine the result."

Surveys show that many voters want to punish traditional mainstream forces for the country's near economic collapse. The centre-left Pasok and centre-right New Democracy have seen their popularity plummet to half of the 77% that they jointly captured in 2009.

Instead, Greeks appear poised to vote for an array of smaller splinter groups that have won support on the back of vociferous opposition to the stringent terms attached to the EU and IMF bailing out Athens' debt-stricken economy.

The neo-fascist Chyrsi Avgi, like the band of satellite communist groups also opposing the harsh terms of austerity in return for aid, have seen their fortunes rise as "anti-memorandum" fury has grown. Shamelessly xenophopic, Chrysi Avgi has become increasingly popular among those hit by steep pay and pension cuts and enraged by illegal immigration with polls showing the party easily crossing the 3% threshold to enter parliament.

Independent Greeks, another unabashedly populist group set up in February by a former New Democracy MP also opposed to the punitive terms of the bailouts, has similarly seen its popularity soar among a populace grappling with deepening poverty and record levels of unemployment.

France

In the first round of the French presidential election a distrust of globalisation and the direction of the European project were clear. Marine Le Pen came third as the far-right Front National took its highest score of 17.9%. New research to be released next week by TriElec at the Paris-based European Studies Centre, at Sciences Po, found 54% of Le Pen's voters favour leaving the European Union and 81% feel that globalisation has negative consequences for France. Le Pen wants to pull France out of the euro.

On the hard left, Jean-Luc Melenchon took 11% on a programme that was vehemently opposed to Brussels's austerity measures and the fiscal treaty. Distrust of globalisation among French voters is high, exacerbated by the decline in French industry, factory closures and record-unemployment.

The frontrunner, Francois Hollande, who must address the high number of fearful blue-collar workers who chose Le Pen, has stressed that renegotiating the European treaty and setting measures to increase growth is the key to protecting France and redressing its troubled economy.

The incumbent, Nicolas Sarkozy, aware of a mood of disillusionment with the political class, has repeatedly promised to address what he calls the France that says no, meaning French people who feel estranged from politics, and also those who voted no in the 2005 referendum on the European Constitution.

Netherlands

Geert Wilders's Freedom party this week effectively succeeded in bringing down the centre-right minority government. The anti-immigration, anti-euro, and more recently anti-austerity party pulled out of the administration, citing its opposition to deep budget cuts. Elections are scheduled for September.

Ireland

Ireland faces a referendum on the EU fiscal pact on 31 May, with opinion polls showing only a slim majority in favour of a yes vote. Foreign minister Eamon Gilmore rejected the notion that a Hollande victory in France would make it harder to make the case for a yes vote. Sinn Fein and other opponents of the treaty have already claimed Hollande's programme is in direct opposition to the austerity policies the Irish government wants voters to endorse at the end of next month.

Italy

Cynical voters the world over complain politics is packed with comedians. But Italy is perhaps unique in having a party leader who is also a professional comic.

Giuseppe "Beppe" Grillo, a shaggy-haired, bearded comedian reminiscent of Billy Connolly, has for years played a mischievous, though essentially minor, role in a corner of the Italian political stage. As far back as 1986 he ran foul of the grey suits at the RAI, Italy's state-owned broadcasting network, over jibes at the then Socialist prime minister, Bettino Craxi.But oOn 6 and 7 May, when partial local elections are held in Italy, Grillo and his strongly anti-establishment Five Star Movement could win as much as 7.5% of the vote, according to a recent poll.

Like other successful outsiders, Grillo has made shrewd use of the digital media. Time magazine chose Grillo's blog as one of the world's 25 best. He has more than half a million followers on Twitter and his Facebook page has attracted almost 800,000 "likes".But critics see the comedian as a rabble-rouser and fear he could be steering his supporters down a dangerous road towards populism.

His Five Star Movement, founded less than three years ago, claims 200,000 enrolled members. Yet it denies it is a party and its charter appears to favour a form of direct democracy that would give "the entire public the role of government and guidance normally attributed to a few".

Germany

One of the most successful "none of the above" groupings is the German Pirates party, which has gone from being "a bunch of computer nerds who have turned into a 13% party", in the words of one commentator. It has won parliamentary seats in two consecutive state elections within a couple of years and with almost one vote in seven can lay claim to being the third most powerful political force in Germany.

It may have some work to do on its PR though: one party member last week said the party's rise was as meteoric "as that of the Nazi party between 1928 and 1933".

The party's raison d'etre can be summed up in a short phrase: supporting internet freedom. Like other obscure groupings in the region, the Pirates don't have much substance in their manifesto, but in that they have become a magnet for disaffected voters looking for an alternative home they are contributing to a reshaping of the political landscape.

That this happening in a mature democracy such as Germany, despite low unemployment and a healthy economy, is also causing heads to turn.

Elsewhere

Governments in the Czech Republic and Romania have come under huge public pressure to step back from austerity. Thousands have protested in both countries recently, calling on governments to abandon belt-tightening measures.

The administration in Bucharest was finally ousted yesterday when opposition parties seized on public anger to vote for a no-confidence motion.

The centre-right Czech government of Petr Necas has come under additional pressure because of an anti-corruption movement, which escalated when a junior coalition partner, the Party of Public Affairs, whose main platforms are transparency and fighting political corruption, split after one of its leaders was convicted of bribery.

Austria's Freedom party has championed the anti-establishment fringe for so long that it is almost becoming part of the establishment. Eurosceptic and anti-immigration, it is currently joint top in polls with the government coalition Social Democrats.

In Poland eyes are on the Palikot movement, a liberal, anti-clerical, populist grouping set up by a former MP for the centrist civic platform. One of its programme points is the distribution of free condoms for all.

Lehet ma a Politika (Politics Can Be Different) is Hungary's offering, a green/liberal party founded three years ago which won seats in the parliament in 2010 and sees its main role as bringing about the reform of Hungarian politics, which currently fits in well in a continent where a growing number of voters are of the firm belief that their leaders have forfeited their trust.

Countries that have lost governments as a direct result of the fiscal crisis:

Finland

17 April 2011 – Parliamentary elections are held ahead of a vote on whether to approve a bailout for Portugal.

With austerity measures being a key issue, the conservative National Coalition party, as the largest party, wins and forms a coalition with six other parties.

Slovenia

20 September 2011 – A no-confidence vote, triggered by internal political and economic crises, in the centre-left minority government, led to early elections being called in December 2011.

The election was won by the Postive Slovenia party, but after MPs failed to accept the party's leader as prime minister, a right-wing coalition government was formed, led by Janez Janša of the Slovenian Democratic party.

Slovakia

11 October 2011 – Prime minister Iveta Radicova resigns after failure among the centre-right governing coalition to agree reforms to the eurozone's bailout package.

When elections are held in March 2012 the social-democratic Smer party, led by Robert Fico, wins.

Greece

9 Nov 2011 – Greek prime minister Giorgios Papandreou resigns, making way for an interim coalition government, which has the enormous task of steadying the troubled Greek economy.

Greece is due its first election since the start of the debt crisis on 6 May.

Italy

13 Nov 2011 – Having dominated Italian politics for nearly 20 years, prime minister Silvio Berlusconi steps down amidst legal woes and contagion from the euro debt crisis. President Giorgio Napolitano asks European Union commissioner Mario Monti to form a government of technocrats.

Spain

20 Nov 2011 – Spain's centre-right Popular party (PP) records an emphatic victory in a parliamentary election dominated by the country's worrying debt crisis.

Mariano Rajoy's new conservative government has begun the difficult task of addressing chronic unemployment in Spain.

Ireland

6 March 2011 – New government, with Fine Gael leader Enda Kenny in charge, takes office. Mr Kenny's centre-right party forms a coalition with the centre-left Labour party. Its immediate task is to negotiate the terms of Ireland's €85bn bailout.

Portugal

6 2011 June – In Parliamentary elections the ruling Socialist party is thrown out. The Social Democratic party assumes control, along with the Popular party. The government is now drafting unpopular plans for the country's biggest spending cuts in 50 years.

Romania

6 Feb 2012 – The prime minister Emil Bloc and his cabinet resign after weeks of protests over corruption and austerity measures. President Basescu asks Mihai-Razvan Ungureanu to form a new cabinet.

The two month old interim government collapses on 27 April after a vote of no confidence following public anger at continuing austerity measures. Elections are set for November.

Holland

23 April 2012 – Dutch prime minister Mark Rutte resigned after far-right leader Geert Wilders refused to support the government's austerity package. A few days later the Dutch government managed to agree an emergency austerity deal.

Elections are set for September.

Additional reporting by John Hooper in Rome, Helena Smith in Athens and Henry McDonald in Dublin