JERUSALEM » When Germany invaded the Soviet Union in June 1941, the wife of Heinrich Himmler, chief of the Nazi Gestapo and the SS and one of the main orchestrators of the Holocaust, sent him a message: "There is a can of caviar in the ice box. Take it."

On another occasion Himmler’s wife, Margarete, received a note: "I am off to Auschwitz. Kisses, Your Heini."

Excerpts from a private collection of hundreds of the Himmlers’ personal letters, diaries and photographs were published for the first time this weekend by the Israeli newspaper Yediot Aharonot and the German paper Die Welt, providing a rare, if jarring, glimpse into the family life of one of Hitler’s top lieutenants while he was busy organizing the mass extermination of Jews.

A team of researchers and writers at Die Welt have been analyzing copies of the papers since 2011, according to the German newspaper’s website. The newspaper described the collection, which is kept in Israel, as "the largest and most significant find of private documents of a leading Nazi criminal."

Die Welt wrote that while the documents "do not change the overall picture of the Nazi reign of terror," they added countless details about Himmler’s personality, his daily life and his world. Die Welt said "signs of Himmler’s immeasurable anti-Semitism and his obsessiveness" were already apparent in the early letters from 1927.

Avner Shalev, chairman of the directorate of Yad Vashem, Israel’s official Holocaust memorial, said in a telephone interview that the collection was "of great historical significance" because it touched on one of the central questions that researchers of the Holocaust grapple with: how human beings could have carried out such an extreme ideology and persuaded so many people to follow them.

"These were not monsters; they were human beings, however twisted," Shalev said of the Nazi leaders, adding that the letters and diaries "might shed light for researchers dealing with this open question."

Shalev said he hoped the collection would eventually be donated to Yad Vashem, where it would be open to all researchers. Officials from the German Federal Archive said they found no reason to doubt its authenticity.

The archive was hidden in Tel Aviv for decades. Chaim Rosenthal, an Israeli artist and collector, told reporters at a news conference in New York in 1982 that he had purchased the collection that year from the former adjutant to Gen. Karl Wolff, who was Himmler’s liaison officer with Hitler and also commanded the SS – the Nazi special police – in Italy. Rosenthal, who had served as a consul for cultural affairs at the Israel Consulate in New York, said he paid $40,000 for the letters, which he said the adjutant had stolen from Wolff’s estate.

The Israeli news media said other versions of how Rosenthal came to own the collection included rumors that he had bought the letters at a flea market in Brussels. According to some accounts, two U.S. soldiers picked up hundreds of letters and documents from Himmler’s home in Bavaria after the war.

Rosenthal, who died in 2012, was said to have kept the collection in his apartment in Tel Aviv. It was sold several years ago to the father of an Israel-based documentary filmmaker, Vanessa Lapa, and is now kept in a bank vault in Tel Aviv.

Lapa produced a documentary, "Der Anstaendige" (The Decent One), focusing on the contents of the collection, which will be shown at the Berlin Film Festival in February. During the course of her research, Lapa said she got to know Katrin Himmler, the granddaughter of Ernest, Heinrich Himmler’s younger brother. Katrin Himmler, an author and researcher who married an Israeli, the son of Holocaust survivors, plans to publish a book based on the Himmler letters.

The collection includes hundreds of personal letters written by Himmler, his wife and their daughter, Gudrun, as well as eight diaries and scores of family photographs. One shows Himmler on a tennis court enjoying a game of doubles.

Himmler was born in 1900 and married Margarete, or Marga, who was seven years older and whose previous marriage ended in divorce, in 1928. In 1929 he wrote of his loyalty to Hitler, telling his wife, "Believe me, if Hitler tells me to shoot my mother – I’ll do that."