Nicholas Winton is often referred to as "Britain's Schindler."

He was a young British stockbroker when, in December 1938, he canceled a trip to go skiing in Switzerland, and instead went to visit a friend in Prague who was helping refugees fleeing from the Nazis.

That visit changed his life — and the lives of many others. Winton went on to save 669 children, most of them Jewish, by arranging their safe passage to England from Czechoslovakia in the lead-up to World War II. Many of the parents they left behind perished in Nazi concentration camps.

Winton was knighted in 2003 and died last July, at age 106. In London on Thursday, some of those he saved — often called "Winton's Children" or "Nicky's Family" — are celebrating his life at a memorial.

Among them is John Fieldsend, born Hans Heini Feige in Czechoslovakia in 1931. When he was a baby, his family moved to his father's hometown of Dresden, Germany.

Then, in 1933, Adolf Hitler won power in Germany.

"When things got too dangerous in Dresden for us, as a Jewish family, we escaped to my mother's parents' home in Czechoslovakia," Fieldsend told NPR in an interview this week at his home in Oxfordshire, about 40 miles west of London.

Then, in 1938, Germany invaded Czechoslovakia's northern and western border regions, known as the Sudetenland — where the Feiges were staying.

"I remember the German army marching through our [Czech] village," he says.

Fieldsend's parents decided to send their two sons, Hans (later renamed John), 7, and Gert (later renamed Arthur), 10, on the Kindertransport — trains carrying children to safety in England.

"My father said, 'Sit down, boys. You're going on a long journey. We can't come with you,' " Fieldsend recalls. "As the train was leaving, my mother took her wristwatch off and gave it to me through the window of the train, and simply said, 'This is for you to remember us.' So they probably knew more than we did."

Fieldsend and his brother were sent to live with foster families in England — with whom they remained through World War II and until adulthood. After the war, they received a package from the International Red Cross with family photos, and, later, a separate letter.

The following is the full text of that letter, a farewell from Fieldsend's parents to their sons. Fieldsend read it aloud to NPR, translating from the original German:

Dear Boys, From MotherWhen you receive this letter, the war will be over, because our friendly messenger won't be able to send it earlier. We want to say farewell to you, who are our dearest possession in the world, and only for a short time were we able to keep you. Fate has not left us for months now. In January 1942, the Weilers were taken; we still don't know where to and whether they are still alive. In June, Grandmother Betty. In September, Aunt Marion, Uncle Willy and Pauli. In October, your Steiner grandparents. In November, your 90-year-old great-grandmother and the Bermans. In December, it will be our turn. The time has therefore come for us to turn to you again, and to ask you to become good men, and think of the years we were happy together. We are going into the unknown; not a word is to be heard from those already taken. Thank those who have kept you from a similar fate. You took a piece of your poor parents' hearts with you, when we decided to give you away. Give our thanks and gratitude to all who are good to you. From Father Your dear mother has told you about the hard fate of all our loved ones. We too will not be spared and will go bravely into the unknown, with the hope that we shall yet see you again when God wills. Don't forget us, and be good. I too thank all the good people who have accepted you so nobly. Signed, Curt & Trude Feige, 1943

Records show the Feiges were interned in the Auschwitz concentration camp on Feb. 26, 1943. The exact date of their deaths is unknown.

"A couple weeks after writing this, they went to the gas chambers," Fieldsend says. "What a letter. Wonderful parents."

Fieldsend and his brother grew up in separate foster families in England, but stayed close. They anglicized their names. John embraced Christianity and became a vicar in the Church of England, a career from which he is now retired, at age 84.

It would take 50 years for him to learn exactly who had arranged his passage to safety.

In 1988, the BBC got hold of a scrapbook, found in the attic of a retired stockbroker named Nicholas Winton.

In it were photos, names and records of hundreds of European children for whom Winton had paid train fares, forged travel documents and arranged foster families in England.

Winton had never spoken about it publicly. But his wife apparently found the scrapbook in their attic, and it eventually made its way to the BBC through other relatives, despite Winton's modesty.

A popular BBC TV program at the time, That's Life, aired a segment about the scrapbook, and a photo of Fieldsend as a boy briefly appeared on TV.

"A friend rang me and said, 'John, were you watching That's Life?' We often watch it, but that night, we weren't watching," Fieldsend recalls. "She said, 'Well, John, you were on it.' "

Fieldsend phoned the BBC and was invited to the studio for the next episode. Winton was there, too. But what Winton didn't know was that the entire studio audience was made up of people whose lives he had saved.

Onstage, BBC presenter Esther Rantzen asked: "Is there anyone in our audience tonight who owes their life to Nicholas Winton? If so, could you stand up please?"

The whole studio audience, several dozen people, stood up.

"It was absolutely amazing," says Fieldsend about that moment when Winton turned around and looked at the room filled with people he'd saved. "He was such a human, ordinary, quiet man. It was amazing."

After meeting on TV, 50 years after Winton had saved Fieldsend, the two men began a belated friendship. Turns out they lived close to one another, and enjoyed pub lunches together in Oxfordshire. Winton attended a 50th wedding anniversary party for Fieldsend and his wife, Elizabeth.

That friendship endured until Winton's death last summer. Fieldsend says he never figured out how to adequately thank him.

"He could have been imprisoned, he could have been shot — anything could have happened to him," Fieldsend says. "He had no reason to be involved. He was just a good British stockbroker."

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