More than 70 years on, we cannot afford to lose the rights hard won for refugees after the horrors of the Holocaust

Every family has subjects that are avoided. Ours was the death of my grandfather, David Kozak, at the hands of the Nazis. I was named after him but we rarely spoke of him. There was a suggestion he was killed in Auschwitz, but little by way of confirmation. We have one picture of him, but we did not know how he perished, or where.

The subject was too painful to discuss, but when I was younger seemed pointless, too. My mother last saw her father when she was five years old. She has only the haziest of memories of him. She had made a new life after the Second World War as a refugee from Poland to the UK. Her mother and sister went to Israel.

Then last year I received an email from a German historical group near Stuttgart. For fifteen years a determined group of volunteers had doggedly pursued the truth about the small labor camp established at Hailfingen in southwest Germany.

That truth included the documentary proof that David Kozak, registered with Auschwitz number 193182, had been transferred from Auschwitz to Hailfingen to help rebuild a German airfield on Nov. 19, 1944. He was given a new number (40705). The Nazis were nothing if not organized. He died there, causes unknown, on Jan. 17, 1945 and was buried in a mass grave, along with 74 others.

Our family (my mother, aunt and brother) recently visited the site and learned about the backbreaking labor, the denial of medical care, the paltry rations, the three mile walks through town to the quarry, all documented by Germans committed to record, learn and teach. I also learned how the story has importance beyond my family, for what it says about how nations come to terms with painful truth—and rise above it.

History needs to be addressed not as an act of masochism but as a passport to renewal. This is not about prosecution of the past; it is about liberation from it. In this the Germans have lessons to teach.

The mass grave containing the remains of David Kozak was exhumed on liberation at the instruction of French authorities. There is a haunting photo of some of the bodies laid out on the ground in a row.

French soldiers insisted that local people do the digging. In the process, two of the diggers died. And so began a narrative of false equivalence about how the townspeople were victims too.

It was the sense that history was being rewritten that motivated a group led by two local teachers to set out to try capture the real truth for posterity. Starting in 2001, when a presentation from local officials whitewashed the history of the camp, they set out to take on local opposition and inertia and establish what really happened.

A sign warns of high voltage near the infamous 'Death Gate' at the Auschwitz II Birkenau extermination camp on November 14, 2014 in Oswiecim, Poland. Getty Images

Now we know, from documentation and from interviews with survivors and local people, about the Jewish prisoners from 15 countries; the prisoners of war who were also conscripted; the 601 deaths. We also know about the local farmers who "accidentally" dropped potatoes and carrots from carts for prisoners to collect on their forced marches, and about the actions of the guards who decided whether prisoners collecting that food should live or die.

We learnt on our visit that it was the direct testimony of survivors that was the "the point of no return" for local townspeople in denial. The ongoing education of successor generations is designed to preserve the truth and learn from it.

The generations of Germans who have toiled to record and learn from their own history, and are determined that it informs their future, are testimony to the power of the truth to produce citizens worthy of those titles.

It is no accident that Germany is leading the charge for humanity and compassion in the refugee crisis. Understanding the truth doesn't just shape what nations are, it directs what they want to be.

Last year's German elections, when the far right Alternative for Deutschland garnered 13% of the vote, show how hard it is. But it is striking how the two right of center German parties who will be the core of the next government have entered coalition talks with a commitment to admit as residents 200,000 asylum seekers per year—fifty times the UK's annual refugee resettlement commitment.

Today's refugees from Myanmar or South Sudan are a different religion from my family. World politics are different. But in Germany and the rest of Europe, in the US and the UK, and in countries that are close neighbors to crisis zones in the Middle East and Africa, the all too familiar lessons of history confront us once again.

An original sign in German reads: 'Warning! High Voltage Danger' at a barbed wire fence at the former Auschwitz I concentration camp on January 27, 2015 in Oswiecim, Poland. Getty Images

For centuries, refugees were not counted and did not count. But after World War 2, because of World War 2, they and their rights were finally recognized in law. The set of rights gained by refugees were written by the western world. Trash the protections for refugees and we trash our own history, and one of our distinctive contributions to global progress.

On the site of the airfield, there is a memorial with the names of all those sent to the camp (not just those who died). It is deliberately shaped as the tip of the iceberg, to symbolize that the ultimate hatred of persecution and killing is built on deeper ignorance and prejudice. History shows us that events can thrust these dark forces to the surface, fracturing the bonds that make us human.

Nearby are the sculptures by local young people inspired by what they have learnt. These sculptures humanize what is unimaginably inhuman. For example, there is a shoe carved from stone, because for the prisoners, forced to walk to work every day in all conditions to prove their usefulness, a shoe was the difference between life and death. It stands as a permanent memorial to those oppressed, and to learn from the truth.

As we witness the rise of populist sentiment across Europe, it should be clear that while the truth hurts, the absence of truth-telling hurts more. The striking example of German confrontation with its past has been far more beneficial to its own renewal strength than the evasions of neighboring Austria.

The truth does not absolve or restore, but it does make it possible to move on. And the longer it is not addressed, the greater the danger of distortion. When truth is buried, it distorts national progress.

"Gegen vergessen—fur Demokratie" (Against forgetting, for democracy) is the name of one of the local groups in Hailfingen. We must face our pasts to move on—and uphold the highest human ideals.

David Miliband (@dmiliband) is president of the New York-based International Rescue Committee. His book Rescue: Refugees and the Political Crisis of Our Time is out now. All proceeds go to the International Rescue Committee.