As the Second World War raged, every night for months on end Brenda Pluczenik would wake up her daughters and their cousin and ask them one question: “What is your name?”

Yona Kobo, the curator of a new online exhibition at Yad Vashem, is in no doubt. “You could not survive as yourself”.

In Remember Your New Name: Surviving the Holocaust under a False Identity (which coincidentally shares a title with the book featured on pages 44-45), Yad Vashem looks for the first time at Jews who survived using fake documents.

Often, like Brenda and her family, they posed as Polish Christians and relied on the help of smugglers or the kindness of non-Jews, who were later named as Righteous Among the Nations.

The use of faked documents was not confined to one geographical area, says Kobo. “It was happening all over Europe and it was one of the ways for Jews to survive.

But it was a route fit only for a few: you had to be familiar with the culture and the language, the customs and the prayers of non-Jews. It wasn’t enough to get false papers and then relax. You had to be smart and resilient, to ignore all traces of your Jewishness”.

In 14 separate stories of individuals and families, ranging from Belgium and the Netherlands to France and the heart of the Nazi machine itself, Berlin, Yad Vashem casts a spotlight on those who survived by pretending to be other than they were.

“It was a daily challenge”, says Kobo. “Sometimes people were pushed from one place to another because there were suspicions that they were Jews and the authorities were alerted.

So people might have to leave in a second, abandoning all their belongings and having to find a new hiding place. Sometimes Jews paid for the fake papers, and sometimes they were betrayed. Other times they were helped and hidden. Each story is unique.”

So who was doing the forging and why? Again, this varied a great deal. Some of those providing fake papers were opportunists, black marketeers who were making money out of the war and did a little casual forgery on the side.

Some were members of the local resistance, often helping to provide documents for Jews who had crossed borders and left their country of origin, because it was too dangerous for them to remain among the local population.

Polish-born Zygmund Fischab, for example, testified to Yad Vashem: “It was possible to obtain a forged ID card (Kennkarte) and a Catholic birth certificate with which to escape from the ghetto and live on Aryan papers.

Jews and Poles would provide these false papers for a fee. Anyone with a ‘good’ appearance, who didn’t look Jewish… had a chance of survival. In general, self confidence was required in order not to arouse suspicion in neighbourhoods where Aryans lived.

Poles known as ‘Schmalzovnikim’ roamed the streets. They had a nose for sniffing out Jews.”

It was particularly hard for Jewish men to evade such people. Often, said Zygmund Fishchab, Jews — even those with false papers — would be dragged into a side alley by local Poles and made to drop their trousers to see if they were circumcised. That, in turn, led to frequent attempts at extortion.

In some cases it was Jews who were saved by other Jews, those who had joined underground units and began “a business”, supplying food coupons or forged identity papers to other Jews. “They would provide fake birth certificates or travel documents”, says Kobo. “That happened in many places”.

One man whose remarkable story is featured in the exhibition is Tony Gryn, a Polish-born would-be medical student who ended up running a forgery workshop in Paris.

He set up a Jewish underground rescue unit in the French capital in 1943, and, according to Yad Vashem, “he established a workshop for forging documents, and a network for them to reach thousands of Jews hiding in Paris and northern France.

“He organised liaisons, who sourced the forms and stamps crucial for the forging operation and obtained them at great personal risk.

"In the workshop… hundreds of stamps were replicated, and different documents were prepared according to names and ID details obtained from municipal offices…

"The forged documents produced included IDs, birth certificates, coupons for food, clothing and tobacco, release papers from the French Army, Disabled Army Veteran certificates, exemptions from forced labour, marriage and death certificates”.

Gryn was later awarded the Légion d’Honneur for his wartime work.

Arye Mayer, a teenager who survived in Berlin under a false name — but without the vital paperwork — spent the war years “running from place to place, like mice, with his mother and sister”, according to Kobo. In the last place Arye and his family lived before liberation, he had been forced to join in with antisemitic denunciations and Hitler salutes.

Yona Kobo shrewdly says there was often a large element of luck, as well as grit and determination by the Jews. Charlotte (née Birnbaum) Weber, who lives today in Jerusalem, survived the war in an obscure village in Belgium, Godinne sur Meuse, together with her mother, her aunt, her brother and her grandparents.

Among the six individuals there were only two sets of fake identity papers, in the names of Charlotte’s mother, Hudes Birnbaum, and her aunt, Rachel Kohn.

The family were taken in by a couple, Joseph and Leonie Morand, who hid them for more than two years, both later named as Righteous Among The Nations by Yad Vashem.

“My mother became a heroine to me”, Charlotte says today. The forged documents sound unlikely to have convinced anyone, since “the original [ID card] had been stamped with a (circular) stamp of the local authority and this stamp also covered part of the holder’s photograph. The new photo now lacked the quarter circle stamp of the original”.

Undaunted, Yeshaya Englander, Charlotte’s grandfather, “who was very artistic”, filled in the missing quarter circle using coloured crayons. Nevertheless, Hudes and her sister-in-law, both young women, defiantly showed these amateurish papers to Wehrmacht officers — and got away with it.

Unlike Brenda Pluczenik’s children, Charlotte, born in 1937, and her brother Henry, five years older, did not assume new names. “I was just Charlotte to everyone. The whole village knew [that we were Jews] and they did not give us away. I was able to play outside with the other children. We were very lucky”.

The family — except for grandmother Leah Englander, who had been ill and who died in hospital in Antwerp before the end of the war — survived and eventually reunited with Charlotte and Henry’s father in London, in 1947.

Perhaps one of the most devastating stories in the exhibition is that of Ida Krayz, who survived among Ukrainian partisans using a false identity.

Ida, who was director of an orphanage in Kiev on the outbreak of war, married in 1934 and gave birth to her son, Welwele-Walentin, a year later. Her husband Jefim was recruited to the Red Army and sent to fight for the Russians.

The orphanage was evacuated deeper into the Soviet Union but Ida did not succeed in getting far enough away from Kiev. She returned to Kiev to rescue her son and mother Miriam, using the name Lidia Wladimirowna Tyszczenko.

But Ida soon learned the tragic news that her mother and son had been taken to Babi Yar, the pit of mass murder on the edge of the city. Neighbours told her: “Two thousand children were buried alive at Babi Yar.

The earth has been moving above those little ones for three days.”

A heartbroken Ida wandered between villages and towns under her assumed Ukrainian identity, in constant danger of being found out and handed over to the Germans. At one point she joined the Russian partisans, “with her dubious credentials and wearing a cross around her neck.”

Extrordinarily, she survived and after the war discovered that her husband Jefim had been killed in the first days of fighting in the Kiev area. She moved to Poland and re-married, to Avraham Pinkert, a Yiddish theatre actor and director. Avraham and Ida had two children, and they moved to Israel in 1957.

Many of the forged documents telling these remarkable stories are on show in the exhibition, which went online this week to mark Holocaust Memorial Day.

The fake papers, saved by the survivors, are incredible fragments of lives saved in the most extreme of circumstances, sometimes on a day where a sliver of coloured pencil could make the difference between life and death.