As President Donald Trump spoke last week in Warsaw, Poland, cable news cameras panned across the raucous crowd bused in by the country’s right-wing government to cheer him on.

Amid the waving red-and-white Polish flags, a lone man ― over 4,000 miles from the U.S. South, from the land of Jim Crow, the Ku Klux Klan and slavery ― could be seen holding the Confederate flag.

Wait a sec, is that a confederate flag, at the Trump speech, in freakin #Poland? What?! Man, every day just gets more and more bizarre pic.twitter.com/0om5cBbim7 — DJ Z-TRIP (@ztrip) July 6, 2017

There was some frightening symbolism to it: a 150-year-old emblem of white supremacy at a seemingly all-white rally for a white U.S. president speaking in dire, white nationalist tones about defending “Western civilization.”

But how did a flag born out of the American Civil War end up at a political rally in Poland in 2017? Groups across Europe have embraced the flag for their respective causes for years, and experts say some of its European fans don’t understand what the rebel flag really represents in U.S. history.

WOJTEK RADWANSKI via Getty Images A far-right activist in Warsaw, Poland, holds a Confederate flag and a White Pride flag while taking part in a July 2015 demonstration against accepting over 2,000 immigrants to the country.

Mark Pitcavage, senior research fellow at the Anti-Defamation League’s Center on Extremism, says Europeans who use the flag can typically be divided into three groups.

First, he said, there are the out-and-proud racists.

“White supremacists in Europe will often use American hate symbols just as white supremacists here will use hate symbols derived from Europe,” he told HuffPost. “I’ve seen Swedish skinheads with Klan and Confederate tattoos.”

Neo-Nazis across Europe ― especially in Germany, where displaying the swastika in public is outlawed ― have been known to use the Confederate flag. And they well know what it means, Pitcavage said.

At an anti-immigrant rally in Poland in 2015, a protester could be seen waving both a White Pride flag and a Confederate flag. And here’s the flag at an anti-refugee rally in Germany that same year:

The second group of Confederate flag-wavers, Pitcavage said, are right-wing political activists, many of whom have separatist inclinations.

The flag, for example, is a common sight at games of the Italian football team Napoli. That’s because many people in southern Italy see common cause with the Confederacy, The Washington Post reported. Both regions once were absorbed or defeated by a larger Northern power ― Rome, in the case of Italy.

Why are the Napoli fans flying the Confederate flag at Stamford Bridge? pic.twitter.com/8qvf0Jat — Our_Arsenal (@Our_ArsenalFC) March 14, 2012

During the Ukraine-Russia conflict, both far-right pro-Kiev groups and pro-Moscow separatists have been seen using the flag, or an approximation of it.

And the Red Hand Defenders, a protestant paramilitary group in Northern Ireland, often march with the Confederate flag. They claim to do so because there were so many Northern Irish troops in the Confederate army.

And further south in County Cork, Ireland, soccer fans are known to wave the flag, seeing parallels between the Confederacy and Cork’s history as a “rebel county” in Ireland’s fight against British rule.

But the most common reason the Confederate flag flies across Europe, Pitcavage said, is ignorance.

“Even Americans are infamously ignorant of the culture and history of other places,” he said. “Many Europeans don’t have a detailed or nuanced understanding of the U.S. and they sometimes get a Confederate flag because it’s a symbol of Americana to them.”

“They don’t understand the racial or dark history of that flag and what it represents,” he said.

Miroslav Mareš, a professor at Masaryk University in the Czech Republic who studies right-wing extremism, agrees.

“In some subcultures [the flag] is used without deeper political meaning,” he told HuffPost in an email. “It is simply a symbol of the ‘way of life’ in the U.S. South (tramping, motorcycle gangs, Southern rock scene etc.).”

One of the clearest example of this is in Sweden, where people involved with the “raggare” subculture are obsessed with Americana ― often wearing cowboy hats and driving around in vintage American cars with Confederate flags. For them, the flag is just another piece of kitsch, divorced from its historical context.

(Skip ahead to 2:08 in the video below.)

Is it possible that using the Confederate flag in this way is due, in part, to the United States’ own failure to reckon with what the flag really represents? Hardly anyone, after all, mistakes the meaning behind the swastika, or waves the Nazi flag from their vintage Volkswagens in an innocent celebration of German kitsch.

Pitcavage said he doesn’t think so. The U.S., he argued, has “outsized cultural influence” across the world, and random American symbols, however imbued with political meaning here, are often reappropriated abroad to simply signify America itself.

This flag sure pops up in the most unexpected of places...Had a chat w/ the shopkeep. His words: It's American, no?. Me: No! #Bangkok pic.twitter.com/cyvGIITofR — PriyaD (@Priaad) July 12, 2017

Mareš, the Czech professor, said in Europe “it is important to ask [Confederate] flag holders about their true motives.” That’s what New Yorker writer Elisa Gonzalez did last week when she saw the man holding the flag at Trump’s speech in Warsaw.

“I then went up to a man draped in the Confederate flag, who told me that he knew what the flag meant in America but, to him, it represented resistance to a federal government that dominated smaller states, as the European Union did Poland,” Gonzalez wrote.

“As for Trump, I am neutral. I am here against the EU and forced migration,” the man told Gonzalez, referring to the EU requirement that member states take in a certain number of the millions of refugees fleeing wars in the Middle East.

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