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The Ravensbrück code

the ingenuity of four girls of the camp told the world about Nazi experiments

Krystyna Czyz

Krystyna Czyz

In the summer of 1942, SS doctors started conducting experiments on Ravensbrück camp prisoner women. This operation was guided by Karl Gebhardt, Heinrich Himmler's personal physician. Prisoners’ legs were carved using pieces of glass and wood and then infected with various bacteria, including tetanus, to study the consequences of battle wounds and test the efficacy of new drugs. Victims were no longer considered as women, but rather as “rabbit”.

Such victims included political prisoner Krystyna Czyz, along with three other girls, who found a way to tell the world cruelties committed by the Nazis in the camp.

Their only contact with the outside was monthly letters they could send to their families. These letters had to be written in German, talk about good living conditions in the camp and pass SS checks. Anyone who dared to deviate from this rule, risked being killed. Young women considered the possibility of bribing a guard, but risks were too high. A more ingenious solution was needed.

They therefore wrote letters to their families, apparently similar to the previous ones. It was Krystyna’s brother who noticed an essential detail: his sister mentioned a book for children, highlighting the intelligence and cunning of the protagonist. Such reference looked extremely strange, until his brother remembered the plot of the book and realized that sentence was hiding a clue.

The protagonist of the story, indeed, was known to be very smart. During the story, he was captured, but he could communicate with the outside using a secret code hidden in the initials of words written in a letter. As it happened in the book, by analysing the initials of some words, Krystyna's family managed to find her hidden message: list moczem, that is “letter with urine”.

When in contact with paper, indeed, urine loses its colour and becomes invisible. However, if paper is heated, its colour reappears. Due to this phenomenon, Krystyna’s message had gone unnoticed in the eyes of the SS, but not of her family. Along the edges of the letter, using a pointed stick dipped in such liquid, the young woman started telling about the terrible experiments conducted on them in the camp. Throughout time, still using this “secret code”, she and other girls communicated the names of the victims, their serial numbers, the types of violence they had suffered and the names of doctors responsible for the experiments. This information was then shared by their families with the leaders of the Resistance, the Polish government in exile in London and the International Committee of the Red Cross. On 7th May 1944, an English radio station broadcasted to the world the content of letters received from Ravensbrück, telling about experiments conducted on prisoners and revealing they knew the identity of individuals who were responsible for that.

In 1945, the Nazis began evacuating Ravensbrück and many prisoners were forced to join the terrible death marches. On 30th April, the Red Army finally freed the camp and remaining prisoners. Guards were captured and tried in Hamburg between 1946 and 1948. Karl Gebhardt, the doctor who guided the experiments in the camp, was sentenced to death during Nuremberg Doctors’ Trial. In all cases, secret messages sent by Ravensbrück young women were used as evidence against torturers.

After the war, Krystyna studied geography and became a researcher at the University of Lublin. She died in 2011.
Letters from Ravensbrück were donated by her family to a Lublin Museum in 2017.

Translated by Valentina Gianoli. 

13 June 2019

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