BREMEN — Murat Kurnaz, a German native of Turkish origin, likes to joke around. And considering his story, the humor can sometimes turn rather dark. Today, he speaks about the journey from the Guantanamo detention facility in Cuba to the Ramstein U.S. air base in Germany at the end of his five-year imprisonment in August 2006. He counted 15 armed guards on that flight, sharing the details of how they tied him up in shackles and handcuffs. "As if I was radioactive and highly explosive," he says with a laugh.

But Kurnaz's laughter still works as a barricade 10 years since he was freed. After his return, Kurnaz spoke widely about his time in Guantanamo, and wrote a book: Five Years of My Life: An Innocent Man in Guantanamo.

For many Germans, Kurnaz is just a bearded Guantanamo inmate they may have seen on television. But for refugees, he is an important part of Germany, now serving as an official cultural and linguistic mediator. He explains to newcomers how Germany functions. Every week he visits six schools for two hours each. He also works in refugee camps. Kurnaz plays basketball and beach volleyball and offers martial arts classes.

Murat Kurnaz's book Five Years Of My Life

In one class, Kurnaz speaks to 17 students from different parts of the world — Syria and Afghanistan, Chechnya and Morocco. Some speak English, a few words of German. Others speak nothing but Arabic, Pashto or Farsi. But Kurnaz can communicate with them. He learned all these languages in Guantanamo from fellow inmates.

The students learn of his story: how he went to Pakistan after the Sept. 11, 2001 terror attacks in order to attend a madrasa for Islamic religious studies, but was sold to the U.S. for a bounty. The Americans held him captive, first in Afghanistan, then for five years in Guantanamo. Kurnaz was tortured. He received electric shocks and was dangled from a ceiling. He was not allowed to sleep for days, was subjected to extreme heat and cold, and almost drowned. A few months later, the Americans learned that Kurnaz was neither a militant from Taliban nor a member of Osama bin Laden's al-Qaeda.

By then, neither Turkey nor the German government would take him in.

There are still people who doubt his innocence, who are afraid of him. Today, he "doesn't really care" – at least that's what he says. What's important to him is that his story is heard and his work is known. In refugees camps, he settles disputes. Sometimes he just listens, and consoles migrants, although it's not technically part of his job description. "I do it out of compassion and humanity," says Kurnaz, 34. He listen to stories of broken marriages, the stress of escape, and what it was like to see relatives die during war.

Kurnaz recently received an invitation to speak at Georgetown University in Washington, D.C. But Kurnaz remains humble. Due to his imprisonment, he feels particularly well-equipped to help refugees with their integration. Although he has no expert knowledge, his story lends him credibility.

U.S. troopers escorting a prisoner inside Guantanamo — U.S. Navy/Wikimedia Commons

Although Turks have lived in Germany for three generations and go back 60 years in the country, Europeans are still suspicious of them. "Why do politicians and the media want to destroy everything?" asks Kurnaz. He doesn't speak of right-wing movements and generally uses a toned-down language.

About the recent string of German terror attacks, including those in Ansbach and Würzburg, Kurnaz says: "You can't decry a whole religion just because some idiots are committing horrible crimes."

Kurnaz doesn't really care about politics but is interested in individuals. He's grateful toward German Chancellor Angela Merkel. She had spoken up for Kurnaz in front of former U.S. president George W. Bush in 2005. "Merkel got me out of there," Kurnaz says. "She wasn't obliged to do that."

Kurnaz has been married for a couple of years now. His wife is also German of Turkish origin, wears a headscarf and radiates self-confidence. They have two children. Kurnaz says it was his faith that helped him through the darkest hours. He has now committed himself to the fight against torture. "There's a lot worse than Guantanamo," he says, referring to news from the Syrian city of Aleppo.

Is he able to sleep peacefully despite his memories? Even a long time after his return to Germany, he preferred sleeping on the hard wooden floor of his room, he says. But since his marriage, he prefers the bed.