PRAGUE, Czech Republic (MarketWatch) — Dark skies are gathering over a swath of formerly communist countries from the Baltics across Central Europe down to the Balkans. The threats are populism and migration — both out-migration and opposition to accepting immigrants.

The demographic challenge is huge. Since the communists’ collapse in 1990, an astonishing 15 million people have left the Baltics, Central and Eastern Europe for a better life in the West. That’s 10% of the population of these post-communist countries situated west of Russia and Ukraine. Lithuania and Latvia have registered 25% population declines, and Romania has lost 17%.

Peteris Zvidrins, a demographer at the University of Latvia, is so alarmed at his country’s population loss that he says, “we’re dying out.”

15 million people have emigrated from Eastern and Central Europe since 1990.

Those who have departed tend to be young, educated and skilled. An International Monetary Fund report says labor shortages caused by out-migration are holding back the region’s economic growth.

Despite losing population, Eastern European countries oppose inward migration.

Timbro, a free-market think tank in Sweden, says authoritarian anti-immigrant populism, mostly from the political right but also from the left, Is on the rise. Authoritarian parties, it reports, have parliamentary representation in Poland, Hungary, Latvia, Slovakia and Bulgaria.

The illiberal trend took hold in Hungary as early as 2010 when Viktor Orban’s euroskeptic Fidesz party regained power. Fidesz has a majority in Parliament. Since 2015, Orban has been vocal in resisting European Union demands that Eastern members share the burden of accepting refugees from Syria and elsewhere. An ardent nationalist, Orban justifies Hungary’s refusal, saying in July that Europe’s Christian identity is threatened and that globalists in the West want to create “a new mixed, Islamized Europe.”

Poland shifted right when the conservative Law and Justice party gained a parliamentary majority in 2015. Like Hungary and the Czech Republic, Poland turned aside EU demands that it settle Syrian refugees. The EU request for burden-sharing on migrants came after Germany accepted nearly 1 million refugees. As with Fidesz in Hungary, Law and Justice has placed limits on media freedom and judicial independence.

Myanmar's Rohingya Muslims Flee Violence

Poland’s economy, meanwhile, continues to be Europe’s star performer. Poland is the only EU country to have avoided a downturn from the 2008 financial crisis.

In the Czech Republic and Slovakia, center-left parties hold sway but anti-immigrant sentiment is strong. The Czech Republic holds parliamentary elections in October. Polls indicate that a newly formed party of billionaire populist Andrej Babis may be the biggest vote getter. The country’s center-left president, Milos Zeman, was among the first leaders in Europe to welcome the election of Donald Trump.

Former president Vaclav Klaus, the architect of the successful Czech economic reforms in the 1990s, has stepped up his anti-EU rhetoric. Still influential in retirement, Klaus said in June, “we refuse to permit the transformation of our land into a multicultural society as we see in France and the United Kingdom.” He denounced the EU migrants decree, saying Czechs will resist and not be “forced into obedience.”

A Gallup survey in May indicated that 70% of Hungarians oppose taking in refugees with smaller majorities agreeing in Macedonia, Slovakia, Latvia, Bulgaria and the Czech Republic.

Because of emigration and steady economic growth, unemployment in the region is low. With only 2.9% unemployed, the Czech Republic has the lowest jobless rate in the European Union.

While conceding that Eastern Europe has registered astonishing economic progress in the 27 years since communism collapsed, the IMF says the convergence of living standards with Western Europe is likely to take longer than had been expected. Wages in Germany and Britain remain much higher than in Eastern Europe and free movement of labor within the EU is the magnet that draws Easterners to the West.

The slow pace of catching up with the West is a major theme of populists. When workers at the giant Volkswagen plant in Slovakia went on strike in June, winning a 14% pay rise, Prime Minister Robert Fico complained that Slovaks are paid one third of what VW workers earn in Germany.

It is too early to say if there is a new fault line in Europe but Timbro, the Swedish think tank, sees danger in the rise of the populism in both East and West Europe. It concludes that the rise of populism “constitutes the biggest change in the European political landscape since the fall of the Berlin Wall.”