As world leaders gather in Poland Monday to commemorate the 75th anniversary of the liberation of the Nazi-run Auschwitz death camp in occupied Poland, Edith Friedman Grosman will be far away in Toronto. On Monday, the energetic 95-year-old, who was on the first official transport of Jews to Auschwitz, plans to live-stream the ceremony from home, but only if she feels up to it.

She’s already returned to Auschwitz four times, and that’s enough.

“I’m glad they’re doing something for Auschwitz 75,” she told The Washington Post. “But they have to do something in 100 years and 125 years, too.”

Friedman Grosman grew up in the village of Hummené, Slovakia, with her parents and older sister, Lea.

Slovakia joined the Axis powers in 1940. Soon, Edith was forced to leave the public high school, and her dad had to sell his glass-cutting business to a Christian, whom he then worked for.

Even amid the Jewish crackdown, it was still a surprise when the town crier announced a new order — all unmarried women 15 and older were to report to the school gymnasium in two weeks.

They were told they would be registering for three months of work in a shoe factory, and that it was their patriotic duty to help in the war effort. But when they showed up to “register,” they were strip-searched, loaded into trucks and taken away. Most were teenagers, some were in their twenties, and a handful of mothers in their forties boarded in place of their daughters. None of those mothers would survive.

Over the next few days, Jewish girls were swept up from all the surrounding villages. By the end of the week, Friedman Grosman, then 17, and her sister Lea, 19, were on the first official transport of Jews to Auschwitz, arriving by train on March 27, 1942.

But who ordered that first transport? And why take girls?

Documentation is lost to history, but Heather Dune Macadam has a theory. Macadam has spent more than 20 years researching and writing about the girls, and recently published a book about them called “999: The Extraordinary Young Women of the First Official Jewish Transport to Auschwitz.”

“My sense is that it was [Heinrich] Himmler, but the Slovak government was certainly party to it,” Macadam told The Post.

Himmler had ordered 999 German women from the Ravensbrück prison to be transferred to Auschwitz to serve as prison guards ahead of the Slovak girls’ arrival, she said. And that number — 999 — which may have been an occult obsession of Himmler’s, matched the number of girls who were supposed to be on that first Jewish transport. (Macadam found that authorities miscounted; in reality, there were 997.)

“The parents, of course, [were] duped,” Macadam said. But “this was a patriarchal society, and you’re more likely to give up your daughter than your son.”

These young women arrived at a pivotal moment in the concentration camp’s history. At first, it had been a Nazi prison for Poles of every ethnicity, then for Soviet POWs. By 1942, the Nazis were focusing on gathering up Jews, though they had not yet started their “Final Solution” — mass extermination.

In fact, the girls’ real job wasn’t to make shoes, but to build the very infrastructure that would convert the camp into a death machine. Over the next year, they were brutally forced to demolish old buildings with their bare hands, empty trash out of frozen lakes and build dozens of new barracks. For clothing, they were given the bloody uniforms of dead Soviet soldiers and a few striped dresses with no undergarments. Their entire bodies were shaved, and their shoes were flat pieces of wood with flimsy cloth ties.

Most of them died that first year — of starvation, disease, beatings, medical experiments and suicide. Friedman Grosman’s sister was sent to a gas chamber after she caught typhus. More than 77 years later, her grief is still deep.

“I saw her there almost dead, and the rats were visiting her,” Friedman Grosman said through tears. “She was a beautiful girl. And nothing is left over of her.”

As the flood of Jewish prisoners arrived, the survivors among that first transport were “promoted” to “easier” jobs, such as moving corpses from the gas chambers to the crematoria, sorting through the piles of clothing, jewelry and luggage taken from the dead, and even typing in SS offices. These jobs came with extra rations that allowed them to survive the war. But surviving also meant watching in horror as their own family members were marched into the gas chambers.

Though Auschwitz was liberated on Jan. 27, 1945, most of the surviving girls weren’t there to see it. As Soviet troops approached, they were forced to go on death marches through feet of snow, then were moved to other concentration camps deep in Germany.

Friedman Grosman was sent to the overcrowded Ravensbrück, then to a smaller camp called Retzow. There it was clear to her the Nazis were losing the war. Guards frequently ran for shelter from bombing raids, at which point Friedman Grosman and the other prisoners would raid the kitchens for food. In the spring, on another march to yet another camp, she and 10 other girls fell behind as the sun was setting, when they passed a small shelter. They ran inside, laid on the flat on the ground, and hid for the rest of the night.

When the sun rose the next morning, they realized they were free — and that the shelter where they sought refuge was an apiary full of bees.

It took Friedman Grosman eight weeks to get back to Hummené. Incredibly, both her parents had survived, as had one of her neighbors, a young man named Ladislav Grosman. Friedman Grosman spent three years fighting tuberculosis at a hospital in Switzerland; she and Ladislav were married soon after her release.

They settled in Prague and had a son. Friedman Grosman went back to school for a biology degree, and her husband became a successful writer. In the 1960s, they left communist Czechoslovakia for Israel; she followed her son to Toronto after her husband’s death in 1981.

Like many Holocaust survivors, particularly female survivors, Friedman Grosman didn’t talk about the horrors she experienced for a long time, and the significance of the first transport was largely forgotten.

“If you look at a lot of Holocaust timelines, they mention the date the first [Jewish] transport arrived, but they almost never say that it was all young women,” Macadam said.

Many female survivors struggled to have children because of the cruelties they were subjected to; plus, other survivors sometimes treated people with “low numbers” tattooed on their arms with suspicion, as though they couldn’t have survived that long without doing something unforgivable. Friedman Grosman’s number was 1,970.

But, Macadam said, as the women’s movement took hold in the 1970s, interest in women’s lives has grown over time. The Shoah Foundation has since found 22 women from the first transport who survived the Holocaust; Macadam has interviewed 20 of them; six are still living.

Nowadays, “Edith is a rock star in Slovakia. Everybody adores her,” when she returns to teach people about the Holocaust, Macadam said.

At her apartment in Toronto on Saturday, friends brought by so many dishes for Friedman Grosman that she worried she would have to throw food away. In between visits, she told The Post she had one message for the world: “Don’t hate. Because hate brings criminality and hate brings death. I saw it, I was there.”

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