Prince William has given an emotional speech paying tribute to Princess Alice of Battenberg, his great-grandmother, who rescued Jews during World War II.

The Duke of Cambridge made the moving remarks at an event marking the 75th anniversary of the liberation of Auschwitz-Birkenau on Jan. 27, Holocaust Memorial Day. In the speech, he told a crowd consisting of Holocaust survivors and those who had lived through other genocides since 1945 about how the princess sheltered the Cohen family in Athens during the war.

Alice, who was Prince Philip's mother, immediately asked about the fate of the Cohen family after the Germans invaded Greece, William said.

Princess Alice circa 1945. Photo: © Evening Standard/Getty Images

"Having been informed by her friends and her lady in waiting about the plight of Mrs. Cohen and her young daughter, the princess decided to offer her hospitality to the two ladies; in fact, to hide them in her home despite the danger this entailed," the duke said.

"The princess put a small, two-room apartment on the third floor at the disposal of Mrs. Cohen and her daughter. It was thanks to the courageous rescue of Princess Alice that the members of the Cohen family were saved. The members of the Cohen family left the residence three weeks after liberation, aware that the virtue of the princess's generosity and bravery had spared them from the Nazis.

Prince William visited Princess Alice's resting place in 2018. Photo: © Arthur Edwards - Pool/Getty Images

"The great-granddaughter of Rachel Cohen, Evy Cohen, said this two years ago: 'My family would not exist without the courageous act of Princess Alice. Her story of incredible courage must keep being told in her memory. My generation, the past generation and the future generation are, and will eternally be, grateful to his great-grandmother Princess Alice for the great act of bravery, risking her own life to take in a family in need."

Kate and William helped light candles at the event. Photo: © Chris Jackson/Getty Images

Duchess Kate was in the audience and was visibly emotional throughout William's remarks. The prince's speech comes a day after the Duchess of Cambridge shared two moving photographs she took of Yvonne Bernstein and Steven Frank, who are Holocaust survivors living in the UK.

Kate's emotional images were inspired by the works of Dutch baroque painter Johannes Vermeer and Anne Frank's diary. Yvonne was at the Jan. 27 event and was seen enjoying a conversation with the duchess in a reception held afterward.

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As part of the commemorations for the 75th anniversary of the end of the Holocaust, The Duchess of Cambridge has taken photographs of two Holocaust survivors with their grandchildren. The first photograph features Steven Frank with his granddaughters, Maggie and Trixie. Alongside his mother and brothers, Steven was sent to Westerbork transit camp then to Theresienstadt. Steven and his brothers were 3 of only 93 children who survived the camp - 15,000 children were sent there. The Duchess also photographed Yvonne Bernstein with her granddaughter Chloe. Yvonne was a hidden child in France, travelling in the care of her aunt and uncle and frequently changing homes and names. The Duchess said: “I wanted to make the portraits deeply personal to Yvonne and Steven – a celebration of family and the life that they have built since they both arrived in Britain in the 1940s. The families brought items of personal significance with them which are included in the photographs. It was a true honour to have been asked to participate in this project and I hope in some way Yvonne and Steven’s memories will be kept alive as they pass the baton to the next generation.” The portraits will form part of a new exhibition opening later this year by @holocaustmemorialdaytrust, Jewish News and @royalphotographicsociety , which will feature 75 images of survivors and their family members. The exhibition will honour the victims of the Holocaust and celebrate the full lives that survivors have built in the UK, whilst inspiring people to consider their own responsibility to remember and share the stories of those who endured Nazi persecution. Portraits ©The Duchess of Cambridge

A post shared by Kensington Palace (@kensingtonroyal) on Jan 26, 2020 at 2:05pm PST

"The harrowing atrocities of the Holocaust, which were caused by the most unthinkable evil, will forever lay heavy in our hearts," Kate said in a statement when her photos were released. "Yet it is so often through the most unimaginable adversity that the most remarkable people flourish."

"Despite unbelievable trauma at the start of their lives, Yvonne Bernstein and Steven Frank are two of the most life-affirming people that I have had the privilege to meet. They look back on their experiences with sadness, but also with gratitude that they were some of the lucky few to make it through. Their stories will stay with me forever.

"Whilst I have been lucky enough to meet two of the now very few survivors, I recognize not everyone in the future will be able to hear these stories first hand. It is vital that their memories are preserved and passed on to future generations, so that what they went through will never be forgotten."

Prince Charles visited Princess Alice's grave on the Mount of Olives in Jerusalem. The Prince of Wales was in Israel and the West Bank to attend the World Holocaust Forum in the Israeli capital, and also stepped out to visit the site Christians believe was Jesus's birthplace in Bethlehem. William has also visited his great-grandmother's resting place, and did so while visiting Israel, the West Bank and Jordan in 2018.

Duchess Camilla also attended a moving service marking the liberation of Auschwitz-Birkenau at the camp itself on Jan. 27. King Willem-Alexander of the Netherlands was also among the representatives who joined more than 200 survivors to mark the somber occasion.