Today, I read a news article which had the following quote:
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As if the despicable experience of the ghetto weren’t enough, [Hilda] Mantelmacher and the others who were in line for slave labor [at Auschwitz-Birkenau] were told to disrobe.
“They took everything away from us,” she said, including their undergarments. “They gave us wooden shoes that caused blisters on my feet that felt like fire.”
The women were issued potato sacks for dresses.
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Women at Birkenau were issued cotton dresses after taking a shower
Note the photo above which shows women who have newly arrived at Auschwitz-Birkeanu. After taking a shower and having their heads shaved to eliminate any lice, that might spread typhus, the women have been issued cotton dresses to wear. Note that the cloth does not have a flower pattern, which indicates that they were not made from American feed sacks.
Few people today would admit to knowing anything about feed sack dresses because that would reveal their advanced age. I was born in 1933, so I am familiar with feed sack dresses, but I have never heard anything about potato sack dresses. My family did not put potatoes in sacks to store them, and neither did anyone else, as far as I know.
In the old days in America, chicken feed was sold in sacks made of thick cotton, which had a flower pattern. Women used these sacks to make clothes for their little girls; one sack was enough to make one dress.
As far as I know, a potato crop in America was never stored in any kind of sack. The potatoes that were grown in a back yard garden were stored in a pile inside a shed in the back yard, not stored in sacks. Only in stores were potatoes put into sacks, as shown in the photo below.

Potatoes in “potato sacks”
As far as I know, no one saved the sacks in which potatoes were stored when they were sold in a store. In my home town, no store sold potatoes because everyone grew their own potatoes in their back yard.
The following quote is also from the news article:
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Because Auschwitz-Birkenau was a death camp, even those who were not immediately sent to the gas chambers would eventually learn of their fate.
One day [Dr.] Mengele announced to Mantelmacher and her fellow-inmates of “A House” that they would be going to the gas chambers the following day.
Through the intercession of a girl named Lydia, whom [Dr.] Mengele had admired for her attractiveness, “A House” was spared for one more day while the occupants of “B House” were sent to the gas chambers instead.
“The trucks came,” Matelmacher said, “and there was screaming and crying.”
Mantelmacher (now between 14 and 17 years of age), because she was so diminutive, initially didn’t qualify and would be sent to the gas chamber.
“He looked at me and said I was too little,” Mantelmacher said. “You can’t work. I started crying.”
Her friend Lydia told her to go to the back of the line and bite her lips to make them red and to pull her cheeks to give them a red glow. However, [Dr.] Mengele recognized her and was about to dismiss her to the gas chamber when Lydia came to her rescue.
“Look, she is a good worker,” Lydia told him as she lifted Mantelmacher’s potato sack dress. “She has good strong legs.”
In Hamburg, the work was to collect bricks from bombed out buildings for use in new structures. It appeared to Mantelmacher that the city’s residents went about their business oblivious to the slave labor.
“When the bombs came, we were so happy,” she said. “I prayed for the safety of the pilots.”
To Mantelmacher and her fellow-laborers, the bombings gave them joy, confidence and hope.
“If the Nazis win the war, none of us would be here,” she continued. “If I die from a bomb, somebody will survive.”
Nevertheless, there was always the overhanging threat that if a person did not work hard, she would be shot, beaten to death or sent to the gas chamber.
Mantelmacher was eventually sent to another camp, Bergen-Belsen, where Typhus and death were rampant. It was originally built to hold 10,000 inmates but by April 1945, that number had risen to 60,000.
“The dead were stacked up,” she said. “My job was to take away the dead.”
End quote
Reichsführer Heinrich Himmler had already opened a special section at the Bergen-Belsen exchange camp on July 8, 1944, where 1683 Hungarian Jews from Budapest were brought. The Jews in the Hungarian section were treated better than all the others at Bergen-Belsen. They received better food and medical care and were not required to work. They wore their own clothes, but were required to wear a yellow Star of David patch.
The Bergen-Belsen camp had different categories of prisoners, and the Hungarian Jews were in the category of Preferential Jews (Vorzugsjuden) because they were considered desirable for exchange purposes.
The first transport of 318 “exchange Jews” left the Bergen-Belsen Hungarian camp on August 18, 1944, bound for Switzerland. On August 20th, the trainload of Hungarian Jews arrived in Bregenz and then went on to St. Gallen the next day.
It seems to me that Mantelmacher was not very accurate in her speech to the school children.