At the invitation of Israeli President Reuven Rivlin, over 40 presidents, prime ministers, royals, and parliamentary leaders from Europe, North America, Russia, and Australia attended the Fifth World Holocaust Forum, which is organised by the World Holocaust Forum Foundation and in cooperation with Yad Vashem, the World Holocaust Remembrance Center.

The commemoration marks the day when the Auschwitz-Birkenau extermination camp in Poland, where the Nazis murdered more than 1.1 million people, 1 million of which were Jews, was liberated by the Soviet Red Army in 1945.

Auschwitz was one of the more than 1,200 concentration and extermination camps that Hitler’s Third Reich established across Europe between 1933 and 1945. Much has been written and published about infamous camps at Auschwitz, Dachau, Bergen-Belsen, and Treblinka, but few, outside of the Balkans, have heard about the Jasenovac extermination camp in Croatia, which was never liberated, but instead saw roughly 1,000 inmates escape in the hope that at least one of them would live to tell the world about the horrors of being imprisoned by the Ustase, the Nazi-aligned puppet government that was appointed to rule a part of Axis-occupied Yugoslavia.

Only about 100 survived of the escapees survived and the story of Jasenovac remains one of the lost tragedies of the Second World War.

Israeli professor Gideon Greif, an expert on Auschwitz, researched the history of Jasenovac, which resulted in his book Jasenovac: Auschwitz of the Balkans. The Ustase-run Jasenovac extermination camp was the size of about 150 football pitches and was established on April 10, 1941, four days after Nazi Germany invaded the Kingdom of Yugoslavia.

The wartime Independent State of Croatia, or NDH, was a Fascist satellite that was created by Nazi Germany and Hitler’s closest ally, Mussolini’s Italy. Under its leader, Ante Pavelic, the NDH wholeheartedly adopted Nazi racial theory and set out to exterminate the Jews, Roma, and Serbs who lived in the areas that were under their control – the Jasenovac camp was built to serve this purpose.

What made Jasenovac particularly cruel was the existence of a special camp for children where an estimated 20,000 Jewish, Roma and Serb children were brutally murdered. The methods used by the Ustase guards to kill and torture the inmates were reportedly so barbaric that even SS chief Heinrich Himmler is believed to have suggested to the Ustashe that industrial killing, i.e. gas chambers, was a “cleaner way” to liquidate victims so that the guards wouldn’t need to use knives, axes, and other handheld weapons against those that they were sending to their deaths.

Menachem Shelah, a historian with the Yad Vashem, the Holocaust museum in Jerusalem, wrote in 1990 that “the crimes committed in Jasenovac are among the most terrible in the entire history of humanity.”

Historians have estimated that between 700,000 to 1,000,000 people were killed at Jasenovac. The Nazis, themselves, recorded up to 750,000 deaths. Since the breakup of Yugoslavia in 1991, the Croatian government has continually insisted that only 83,000 people were killed at Jasenovac. Croatia’s first post-Yugoslav president, Franjo Tudjman, an unabashed nationalist and the man responsible for restoring the Ustase-era flag as the national symbol of Croatia, insisted until his death in December 1999 that a mere 3,000-4,000 people died while imprisoned at Jasenovac.

The total number of deaths that occurred at Jasenovac may never be known as concerted attempts to suppress the extent of the horrors of the camp continue to this day. This, however, is not a new process. Immediately after World War II, Yugoslavia’s Communist leader, Josip Broz Tito, played down the crimes that were committed at Jasenovac as they were seen as a potential threat to the “brotherhood and unity” doctrine of Tito’s Yugoslavia.

The result of that policy was that several generations of Croats were never forced to face up to the Ustase’s dark legacy. From the time of the end of the war until the moment when the Socialist Federated Republic of Yugoslavia ceased to exist, Croatian was allowed to adopt a policy of silent deniability and to view its role in the war as simply being on the side who lost rather than having taken an active cog in the extermination of whole populations.

Croatia’s post-war and post-Communist vow of silence regarding the crimes of the Ustase has allowed much of today’s Croatian society to countenance the regular cries of “Za dom spremni” (“Ready for the Homeland” in Serbo-Croatian), an Ustase slogan from World War II that is the rough equivalent to the Nazi’s “Sieg heil”.

That same Ustase salute was engraved on a plaque installed in 2016 by a veteran’s organisation at the memorial complex in Jasenovac, which was later unveiled by Croatian politicians for the Croat soldiers who fell in the Yugoslav Wars of the 1990s. This was, of course, an extremely bitter insult to the memory of the tens of thousands of Jews, Serbs, and Roma who perished here.

Both Jewish and Serbian organisations, which include survivors and their descendants, have boycotted the annual commemoration at Jasenovac since 2016, largely because of the Fascist slogans on the memorial and the fact that the Croatian government continues to play down the truth about its Nazi-aligned past.

Neo-Facisct groups from Croatia annually gather for their biggest meetings in Beliburg, Austria, but the Austrian government has finally forbid the use of Ustase iconography. Unlike in Austria, however, the Croatian government still allows radical groups to openly use Fascist symbols at their rallies. This is, of course, unacceptable for a country that is a member of the European Union, particularly one that only recently chaired the presidency of the EU council.

In December 1970, Willy Brandt, then-West Germany’s chancellor, travelled to Warsaw, Poland where, before the the Monument to the Ghetto Heroes, he dropped to his knees and, in effort to repent, he begged for forgiveness for Germany’s crimes during the Nazi era.

To this day, not a single Croatian official has ever knelt before the Jasenovac monument and either repented or asked for forgiveness for the heinous crimes against humanity that were carried out by Pavelic and his Ustase followers.

That act of denial on the part of Croatia’s government is a reminder that the Holocaust, and all of its horrors, must never be trivialised or forgotten.