Refugees, mostly Syrians, walk through fields in northern Greece as they travel toward the Macedonian border on Aug. 13. (Joe Sinclair/AFP via Getty Images)

Here's a stark illustration of Europe's migration crisis: The Slovakian government recently announced that it would help share the burden of the influx of tens of thousands of migrants into Europe by taking in 200 Syrian refugees. That's a small number, but it was made all the more glaring by another stipulation — these refugees had to be Christian.

"In Slovakia, we don’t have mosques," an Interior Ministry spokesman told the Wall Street Journal. Therefore, the official said, "we only want to choose the Christians."

[Syrian war creates more than 4 million refugees, U.N. says]

International organizations and humanitarian groups have in recent months sounded a warning on the gravity of the refugee crisis. Last month, the United Nations announced that the Syrian civil war had forced more than 4 million Syrians to flee their country. Hundreds of thousands have attempted to find sanctuary in Europe, many braving perilous crossings over the Mediterranean.

On Tuesday, the European Union's border agency reported that 107,500 migrants had crossed into the E.U. in July, a record figure that was triple the number of crossings reported in July 2014.

One of the major havens for these refugees is Austria, which has the highest number of asylum-seekers per capita in Europe. It is projected to see 80,000 migrants arrive this year alone.

Neighboring Slovakia has been pressured by European Union officials in Brussels to help share the burden, but its government, like those of other Central and Eastern European states, has bristled at the demands. From Estonia to Hungary to the Czech Republic, politicians, particularly from right-wing parties, have voiced opposition to accommodating the influx.

"Left-wing policies have led to illegal immigrants flooding Europe, threatening European countries with an unprecedented social, economic, cultural and security conflict," said a statement last week from the ruling conservative, nationalist party of Hungarian Prime Minister Viktor Orban.

[Hungary's response to the migrant crisis? A massive fence.]

Orban's government plans to build a vast barrier along its border with Serbia to better keep migrants out.

The cultural complaint — that, unlike societies in Western and Northern Europe, these nations are less able to adjust to multiculturalism — is most common.

In the Czech Republic, a group called the Bloc Against Islam collected 145,000 signatures for a petition against Muslim immigrants, according to the German DPA news agency.

Although Muslims make up less than 1 percent of the population of many of these Eastern European states, the paranoia over their presence has led to a spike in protests and bigoted rhetoric. Earlier this year, a leading far-right Czech politician encouraged his countrymen to breed piglets and walk the animals near mosques.

Czech President Milos Zeman was more moderate in his rhetoric, but the subtext was clear. "Refugees from a completely different cultural background would not be in a good position in the Czech Republic," he was recently quoted as saying by a spokesman.

As the Journal reports, Zeman's Slovak counterpart, Robert Fico, has made similar noises. When explaining to an Austrian newspaper last week why the number of migrants his country would take in was far fewer than the 1,100 requested by Brussels, he said it wasn't Slovakia's responsibility to welcome the refugees of conflicts his country had no role in fighting.

"I only have one question: Who bombed Libya?" said Fico, referring to the 2011 NATO intervention against the regime of Libyan dictator Moammar Gaddafi. "Who created problems in North Africa? Slovakia? No."

That argument is reinforced by public opinion. A Slovak village near the capital, Bratislava, recently held a referendum on whether to temporarily house 500 asylum-seekers in a nearby facility. Ninety-seven percent voted no.

It's clear that cultural concerns underlie this opposition. They were voiced by Fico himself in January.

"Since Slovakia is a Christian country, we cannot tolerate an influx of 300,000-400,000 Muslim immigrants who would like to start building mosques all over our land and trying to change the nature, culture and values ​​of the state," he said.

Muslims make up 0.2 percent of Slovakia's more than 5 million people. Last year, Slovakia granted asylum to 14 people.