Imagine you just appeared, as if from nowhere – a three-year-old orphan with no parents, no history, no idea of your nationality. Now imagine you had to live with that mystery for your whole life – not knowing where you came from or who you really were. This is what happened to Kari Rosvall.

She calls the first three years of her life the dark years, and that’s what they were until something happened recently in her home in south Co Dublin that changed everything – a clue from the past, about where she came from, a reality she could never have imagined possible.

A letter arrived at her house. Inside was a photograph of Kari as a baby, the first photograph she had ever seen of herself as an infant. At the time, she was 64 years old. The photograph was taken by the Nazis.

Kari discovered that she was born as part of a Nazi breeding programme during the second World War. Lebensborn, “the spring of life” programme, was a secret SS project designed to create a so-called Aryan race of blond-haired, blue-eyed children who would be the future leaders of the Third Reich. Kari Rosvall was one of those Lebensborn children. This is the secret that had been kept from her, for her entire life.

The Lebensborn programme was the brainchild of Heinrich Himmler. Himmler was obsessed with eugenics and the idea of a master race. He once said, “Should we succeed in establishing this Nordic race, and from this seedbed produce a race of 200 million, then the world will belong to us”.

This meant that at the same time that the Nazis were killing Jews as part of the Final Solution they were secretly breeding their own “Aryan race”. The Lebensborn extended beyond Germany, into countries like Norway, where Nazi soldiers impregnated Aryan looking women. Kari’s mother was one of these women.

As part of this plan, Kari was taken from her mother in Norway, when she was just 10 days old, packed in a crate and sent to Germany. There she was kept for the first year of her life with other children chosen for Himmler’s scheme in a Lebensborn home called Hohehorst.

When the war ended in 1945, everything changed. The children who were to be “the elite” suddenly became outcasts in every country. Nobody wanted this sinister reminder of Hitler’s regime. Manufactured by the Nazi war machine, Kari found herself homeless in the world, hidden in an attic with other Lebensborn children. Following a heroic rescue by the Red Cross and a period in an orphanage, she was adopted and grew up in Sweden and eventually found a home in Ireland. But questions from her past still haunted her and she decided to find the answers no matter how difficult this would be.

In her early twenties, Kari had tried to piece together her life story. Like many adopted children she longed for answers, and went looking for her birth parents. She discovered her biological mother in Norway and went to meet her. The meeting was difficult and shocking, and left her with more questions than answers.

Today Kari is an Irish citizen living an ordinary suburban life in Dublin’s Ballinteer. But she has travelled a long way to get there. This is the journey as told in the book, Nowhere’s Child. It is the story of a child abandoned in the world. But it is also a story of a mother and a daughter and of strong people who come to one another’s rescue. It is a story of hope. But it is also a horror story about the shocking reality of an evil regime.

Kari’s story spans the period from the Second World War up to modern-day Dublin. It is a firsthand account that will be gone after this generation. I was lucky enough to meet Kari just over a year ago – almost by accident.

I was reporting for the Pat Kenny Show on Newstalk radio. As a journalist you sometimes think you have to travel to war zones and battlefields to find interesting stories, but sometimes you find them where you least expect.

One day, Kari was at an Irish Countrywomen’s Association meeting, telling her story to some of the ladies who were gathered there. I heard about her from people who were at the meeting, so I went to Kari’s home in Ballinteer to try to find out more.

She told me about her life – about everything that had happened to her – and the interview went out on air. People texted the programme in huge numbers. They wanted to know where they could hear more, and if there was a book about her life.

Kari and I talked about it, and she decided that it was time to tell her story in full, for the first time, and the idea for Nowhere’s Child was born. We both cared deeply about this story and knew it was something that had to be told. And so, we made another decision that would change both our lives. For the next year we would put everything on hold. Kari cancelled travel plans, and I quit my job in Newstalk.

We knew it would be difficult. There were a lot of very painful memories that would have to be relived: Kari’s search for answers, the abandonment by her birth mother, being an orphan in the world and all the feelings that go with trying to come to terms with being part of a history you have not chosen. It would be hard; we knew that. But what we didn’t know was that it would also be healing and inspirational. There were tears along the way, long conversations into the night, gallons of tea, and glasses of wine. And lots of laughter, too.

Kari is one of the warmest people I have ever met. Everywhere we go she brings a warmth and love of life with her. Her optimism is contagious. I do not know how she has found it in her to forgive and put the past to rest. She told me she wants to tell this story to show other people that there is hope and light, even in the darkest places.

Kari has found a home here in Ireland. It is where she is at peace in the world. She is surrounded by loving friends and family, who all came out in great numbers for the launch of Nowhere’s Child just a few short weeks ago. It is a testament to the life she has built with her husband Sven and her son Roger.

Kari Rosvall was just an ordinary person, going about her day. We may have passed her in the street, or in the shops, not knowing the story she had to tell. If there is something we can learn from Nowhere’s Child, it is that history is all around us. It is not some dusty thing from the past. It is a living thing. History is in people. We just need to take the time to stop and ask people what they have experienced, and how they feel about it all. We might just be surprised at what they have to say.

Nowhere’s Child by Kari Rosvall with Naomi Linehan is published by Hachette Ireland, £13.99