They are, if nothing else, a tangible testament to a father's love. From 3 February 1939, when "little Heini" arrived in Swansea after leaving Berlin for the last time, until 31 August, when war made such communication impossible, Max Lichtwitz wrote a stream of postcards to his young son. They have left a unique record of his determination to maintain the parental bond with the boy whose life he had saved by sending him to a strange country and parting with him, as he feared, for ever.

What can the journey have been like for a bewildered six-year-old? Henry Foner, as little Heini Lichtwitz would become, remembers the German border guards searching the train passengers and his one small suitcase, the Dutch women on the other side of the crossing handing out "delicious" sausage rolls, a helmeted bobby on the quay at Harwich, the large hall where he waited to be collected, but nothing of the painful departure from Berlin. "It's a strange thing; if you talk to people like me, the traumatic memory is of parting with their parents, and I can't remember it at all. It must have been traumatic and I must have forgotten because I remember the journey very well, but I can't remember saying goodbye to my father and my grandmother." (His mother had died two years earlier.)

The "people like me" to whom Foner refers were the 10,000 Jewish and "non-Aryan" children of the "kindertransport" who, between December 1938 – in the wake of the Kristallnacht pogrom which had terrorised Jews across Berlin – and September 1939, escaped the coming Holocaust, leaving their families in Nazi Europe by train and ferry for Britain, accompanied by youth workers and unemployed Jewish professionals who risked their lives by returning again and again to remove other groups of children to safety.

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In a series of events to commemorate the programme's 75th anniversary, some of the children, most now in their eighties, will convene with their families at London's Jewish Free School today in a gathering addressed by David Miliband and Maureen Lipman, and at St James's Palace tomorrow for a reception given by the Prince of Wales.

The young Heinz Lichtwitz, as he then was, was destined for the home of a Jewish couple in Swansea, Morris and Winnie Foner. Despite the comforting postcard with "1,000 kisses" his father sent him as soon as he knew he was safely with the Foners, his arrival cannot have been easy. He spoke only German, his new foster family only English and Yiddish.

Yet after just a few months in a local Swansea school, when his father telephoned him on his birthday in June – Henry can remember the call standing in the hall of the Foners' home in the Sketty area of Swansea – he had forgotten his German. Which is why from then on, his father wrote the cards as frequently as ever, but in English. The cards his father sent have now been published, along with other letters and cards, in a book produced by the Israel Holocaust History Museum Yad Vashem, entitled Postcards to a Little Boy: A Kindertransport Story.

They are a rich document of a programme which, when finally approved, was a kind of compromise by a UK government that was at the time resisting demands for an increase in Jewish immigration to British-run Palestine. Not all the children, billeted in homes and hostels across the country, had a happy time.

But Henry Foner, by his own account, was "one of the ones who was lucky. Morris and Winnie Foner brought me up as they would have brought up their own child, and more than that you can say of no-one." They made sure he knew them as "Uncle Morris and Auntie Winnie". "They never tried to hide the fact that I had a father and they would say, 'Henry, after the war we'll have to see…'" But Henry was never to see his father again. The last direct communication he had from Max, a lawyer who had worked hard to help other Jews escape from Germany, was a letter sent through the German Red Cross in August 1942, saying: "I'm glad about your health and progress. Remain further healthy! Our destiny is uncertain. Write more frequently. Lots of kisses, Daddy."

Max Lichtwitz was deported to Auschwitz on 9 December, and killed a week later. But in 1961, shortly before his 30th birthday, Henry received from a second cousin in the US what Max himself, by now expecting the worst, had called a "kind of farewell letter", written in 1941: "I think my Heini has found a good home and that the Foners will look after him as well as any parents could. Please convey to them, one day when it will be possible, my deepest gratitude for making it possible for my child to escape the fate that will soon overtake me… Please tell him one day that it was only out of deep love and concern for his future that I have let him go, but that on the other hand I miss him most painfully day by day and that my life would lose all meaning if there were not at least the possibility of seeing him again someday."

Henry Foner went on to serve in Egypt in the RAF, graduate – and gain a doctorate from – Leeds University, get married and finally settle in Israel with Judy, his beloved wife for 52 years. There, he worked as an eminent analytical and environmental chemist on the Geological Survey of Israel. He has eight grandchildren. The Yad Vashem book is dedicated – as well as to his wife – "to the memory of my father and grandmother who had the foresight and courage to send me away, and to Morris and Winifred Foner who saved my life and made me part of their family."