Seventy-five years after the liberation of Auschwitz, a dwindling number of elderly Holocaust survivors gathered at the former German Nazi death camp in Poland on Monday to honour its more than 1.1 million mostly Jewish victims and to share their alarm over rising anti-semitism.

More than 200 survivors came from across the globe to the camp the Nazis built at Oswiecim in then-occupied Poland, to share their testimony as a stark warning amid a recent surge of anti-semitic attacks on both sides of the Atlantic, some of them deadly.

Survivors dressed in blue and white striped caps and scarves symbolic of the uniforms prisoners wore at the camp, passed through its chilling “Arbeit macht Frei” (German for “Work makes you free”) black wrought-iron gate.

Accompanied by Polish President Andrzej Duda, they laid floral wreaths by the Death Wall in Auschwitz where the Nazis shot dead thousands of prisoners.

“We want the next generation to know what we went through and that it should never happen again,” Auschwitz survivor David Marks, 93, said earlier at the former death camp, his voice breaking with emotion.

Thirty-five members of his immediate and extended family of Romanian Jews were killed in Auschwitz, the largest of Nazi Germany’s camps that has come to symbolise the six million European Jews who died in the Holocaust.

From mid-1942 the Nazis systematically deported Jews from all over Europe to six camps — Auschwitz-Birkenau, Belzec, Chelmno, Majdanek, Sobibor and Treblinka.

Organisers insist that Monday’s memorial ceremony must focus above all on what survivors have to say rather than the bitter political feuds that have tainted the run-up to the anniversary.

“This is about survivors, it’s not about politics,” Ronald Lauder, head of the World Jewish Congress, told AFP in the Auschwitz camp, now a memorial and state museum run by Poland.

“We see anti-semitism rising now and we don’t want their (survivors) past to be their children’s future, or their grand children’s future,” he added.

Royals, presidents and prime ministers from nearly 60 countries will attend the ceremony, but no top world leaders, some of whom opted instead to attend a high-profile Holocaust forum in Israel last week seen as rivalling the ceremonies in Poland.

Poland’s President Duda boycotted the Jerusalem forum after he was denied the opportunity to speak there while Russian President Vladimir Putin was given the floor, despite having earlier falsely accused Poland of colluding with German Nazi dictator Adolf Hitler and contributing to the outbreak of World War II.

While the world only learned the full extent of its horrors after the Soviet Red Army entered the camp on January 27, 1945, the Allies had detailed information about Nazi Germany’s genocide against Jews much earlier.

In December 1942, Poland’s then London-based government-in-exile forwarded a document, titled “The Mass Extermination of Jews in German Occupied Poland”, to the Allies.

The document included detailed accounts of the unfolding Holocaust as witnessed by members of the Polish resistance, but drew disbelief and only muted reactions from the international community.

To inform the Allies, Polish resistance fighters Jan Karski and Witold Pilecki famously risked their lives in separate operations to infiltrate and then escape from Nazi death camps and ghettos in occupied Poland, including Auschwitz.

Regarded as exaggeration and Polish war propaganda, “a lot of these reports were simply not believed”, renowned Oxford historian Professor Norman Davies told AFP.