Newly discovered letters reveal the increasingly desperate efforts by Anne Frank’s father to get his family out of Nazi-occupied Amsterdam before they were forced into hiding in the attic where the teenage girl wrote her famous diary.

Otto Frank sought the help of a rich friend from the family that founded Macy’s department store in New York in an attempt to obtain a US visa.

“I am forced to look out for emigration and as far as I can see USA is the only country we could go to,” he wrote to his friend Nathan Straus Jr in New York on April 30, 1941.

“Perhaps you remember that we have two girls. It is for the sake of the children mainly that we have to care for. Our own fate is of less importance,” he added.

Three typewritten letters from Frank were among nearly 80 pages of material discovered in the archive of the YIVO Institute for Jewish Research by a volunteer seeking to correct a clerical error — the failure to list the subject’s date of birth on the outside of a manila envelope.

“Anne Frank could be a 77-year-old woman living in Boston today — a writer. That is what YIVO’s documents suggest,” Richard Breitman, a professor at the American University in Washington who has studied the document cache, said yesterday.

“The Frank family probably could have gotten out of the Netherlands even during much of the year 1941. But the decision to try hard came relatively late. The Nazis made it harder and harder over time and, by that time, the American Government was making it harder and harder for foreigners to get in.”

Anne Frank kept her diary from June 12, 1942, to August 1, 1944 — three days before the eight people hiding in a secret annexe at the Amsterdam house were rounded up by the Nazis.

Anne, then 15, and her older sister, Margot, were shipped first to Auschwitz and then to the Bergen-Belsen concentration camp, where they died in a typhus epidemic in early 1945. Their mother, Edith, died at Auschwitz.

Otto Frank survived the war when Auschwitz was liberated by Russian troops. After returning to Amsterdam, he published his daughter’s diary, which was found strewn over the floor by two secretaries working in their building.

The letters released yesterday show that he began making plans for his family to hide about the same time he started trying to escape from the Netherlands. The family finally went into hiding on July 6, 1942.

David Engel, a New York University professor of Holocaust studies, said that the trigger may have been a blackmail attempt by a Dutch Nazi official over a casual remark Frank had made to a Nazi sympathiser expressing doubt about a Nazi victory.

“There is a considerable amount of indirect evidence that on April 18, 1941, that is to say 12 days before the first letter to Nathan Straus Jr, Mr Frank was approached by a member of the Dutch Nazi party with a letter of denunciation that had been made against him by one of his former employees,” Professor Engel said. “The Dutch Nazi that was charged with taking this letter of denunciation to the proper authorities instead decided to use it as a lever for blackmail.”

But Teresien da Silva, head of collections at the Anne Frank House in Amsterdam, said that the blackmail attempt was “unproved” and Frank’s attempts to emigrate might simply have been triggered by the worsening conditions for Jews a year after the Nazi invasion of the Netherlands.

Frank, who ran a pectin-supply business in Amsterdam, had considered fleeing before the war to Britain, where his brother Robert was an art dealer. The new letters reveal that he had also applied for a US visa in 1938.

After the Nazi invasion, he turned to his two brothers-in-law in America — Julius and Walter Hollander — who sought the help of their employer outside Boston in raising money for the family’s escape.

Frank also appealed to Straus, the son of the Macy’s founder, with whom he had studied at Heidelberg back in 1908.

In his second letter to Straus, on September 8, 1941, he outlines his plan to seek a Cuban visa in an apparent attempt to travel to Spain or Portugal to try to obtain a US visa from the US Consul there.

“. . . visas for the USA cannot be obtained here but there is no chance to leave the country without a visa. The only way to get to a neutral country are visas of other states such as Cuba,” he writes.

“. . . Edith urges me to leave alone or with the children. I hate this idea but it has to be considered,” he says.

His last letter to Straus, dated October 12, 1941, says: “The situation is getting more difficult every day and you can imagine I am anxious to get your further news as I know that I shall never be able to leave without your help.”

The Cuban Government issued a visa for Frank alone on December 1, 1941, but it was cancelled ten days later when Germany declared war on the United States.

Diary of a teenager in hiding

Anne Frank was born to German-Jewish parents on June 12, 1929

During the Nazi occupation of the Netherlands, Anne and her family spent 25 months hiding in a secret annexe to her father Otto's office. Anne’s diary is a record of this period

The diary was first published in 1947, after a struggle with the director of Amsterdam publishing house Contact, who felt Anne wrote too freely about her sexuality

The first print sold out, a second followed within the year, and the third ran to 10,000 copies

The diary has since been translated into more than 65 languages, and has sold more than six million copies

Anne herself, looking ahead to the publication of her diary, made a list of pen names to disguise the people she wrote about. Some were preserved: the Van Pels, for example, appearing as the “Van Daans”

In 1998 Cornelis Suijk (former director of the Anne Frank centre) announced his possession of five unseen diary pages. Torn out by Otto Frank, they are especially critical of Anne’s mother

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