With Germany's Federal elections returning the country's far right into parliament for the first time in generation, Spanish authorities cracking down on Catalan's independence movement and Italy's anti-EU '5-Star' party riding high in the polls, Europe's political vulnerability is suddenly back in the headlines just as it economy appears to be turning the corner.

The Alternative for Deutschland (Afd) party was by far the biggest gainer in Sunday's federal German elections, boosting its support by more than 8.5% and earning 13.5% of the national vote. Under Germany's electoral system, that's likely to translate into around 90 seats in the Bundestag, making it the third-largest sitting political party in the parliament of Europe's biggest and most important economy.

The far-right's gains could color Chancellor Angela Merkel's attempts to form a coalition government, and possibly force her to take a more inward-looking approach to Germany's financial and political relationship with Europe as she reaches out to her FDP and Green party rivals, each of which have expressed various levels of concern with the Brussels consensus of "ever closer Union".

The potentially game-changing decision in German, which saw formerly "fringe" parties garner nearly a fifth of the electorate's support, followed just a day after Italy's anti-European 5-Start Movement elected a new leader to take the group into Italy's parliamentary elections next year with a consistent lead in national polls over the ruling Democratic Party.

Luigi Di Maio, a polished 31-year-old politician with an electoral appeal that's far more palatable than the party's former leader, 69-year old ex comedian Beppe Grillo, could actually score 5-Star's biggest ever advance in November with a win in the southern regional of Sicily that could lead to a broader parliamentary victory in early 2018.

All of this comes against an at-times violent crackdown on the brewing political crisis in Catalonia, where the country's richest region is planning a referendum on independence from Madrid that the central government has insisted violates Spanish law.

Unless Prime Minister Mariano Rajoy suspends the region's autonomy, particularly with respect to police and security services, Catalans will vote next Sunday in a plebiscite that could, at the extreme, lead to the separation of Europe's fourth-largest economy.

The collection of political challenges follows only months after Europe's ongoing "crisis" was declared dead following the decisive victory of France's reform-focused President, Emmanuel Macron, in May amid a tide of pro-European support from French voters and simultaneous rejection of the far-right Front National.

Furthermore the simmering challenges on the Continent come just as the world's biggest economic bloc is attempting to broker a conclusive separation agreement with its biggest trading partner - the United Kingdom - that must strike a delicate balance between maintaining fluid commercial and political ties while simultaneously sending a strong enough message to discourage other member states from considering similar "go-it-alone" tactics.

Market reaction thus far, however, has been tame, largely owing to both the region's rapidly-improving economy and the myriad safety measures put in place by both EU officials and the European Central Bank, including bailout mechanisms, zero interest rates, quantitative easing and modest political reforms.

Benchmark German 10-year bund yields, a proxy for Europe's "risk free" rate, have risen around 15 basis points so far this month to 0.45%, but that's been largely a result of the U.S. Federal Reserve's interest rate signalling and speculation that the ECB will start to normalise its own monetary policy stance in the near future - in part because of the improving economic backdrop.

In fact, only last week, Portugal's 10-year government bond yields traded at the lowest level -- 2.40% -- since the peak of the region's 2012 debt crisis after it regained an investment grade credit rating from Standard & Poor's.

With the region's manufacturing sector humming along at its best pace in 6.5 years and third quarter GDP expected to grow at an annual rate of around 2.6% or 2.7% this quarter, Europe's efforts towards buttressing its systemic fundamentals may well have provided enough support to weather the current resurgence of political risks.

But those risks are indeed accelerating, and the pace is suddenly worrying.

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