After 12 of his relatives were killed in a single night, where was his anger and pain? And what does his refusal to permit himself these feelings mean for me?

I don’t know when I first heard my grandfather’s story. But I do remember the little green book with the white cross on it. The book was kept in a black steel cabinet in our living room, one that was usually locked, its contents mysterious. There must be important things in there, I thought, that were not for me to see.

My paternal grandparents were part of my childhood; my sister and I called them Oma and Opa and paid them regular visits, but we knew very little about our mother’s parents. They were long dead: my grandmother in 1972, my grandfather in 1979, six years before my birth. The only proof of their existence was a faded black-and-white photo embedded in a glass hemisphere, which my mother kept on her bedside table. In the picture, my grandmother is wearing a high-necked dress and a pearl necklace, and my grandfather a suit and tie, their faces radiating severity. They looked, to my child’s eyes, the way I imagined people from the olden days did; they were from a different world, a different time. I knew my grandmother had been a nurse, and my grandfather a pharmacist, and that they had run a retirement home together near Bremen in Germany. We never visited their grave.

For as long as I can remember, I have felt a weight resting on me; a sadness that has always been part of me, but also feels as if it doesn’t belong to me. I am not the only member of my generation of the family to feel this way: one relative remembers having a recurring nightmare, even as a small child, in which all the people around her are shot. She pretends to be dead and is the sole survivor. And while there has been plenty of trauma in the two branches of the family – war, forced expulsion from East Prussia, violence – one story overshadows everything else: a 12-fold murder.

On the night of 20 November 1945, my maternal grandfather’s entire family, including his four children, were killed on their farm in Blockland, on the outskirts of Bremen. My severely injured grandfather was the only survivor. Years later, he started a second family, from which I am descended. The killings went down in history as the “Blockland murders” and were the subject of detailed press coverage at the time, and again in the 1960s, when a number of those involved were pardoned. My grandfather documented the events of that night in the little green book, but he never talked to my mother and his other children about it. The more the murder was reported, the greater the silence within the family. None of my grandfather’s four children remembers when and how they found out about his first, murdered family. No one talked about it at home, and they never asked.

Facebook Twitter Pinterest Heinemann’s grandparents in a paperweight kept beside her mother’s bed. Photograph: Eva Tuerbl/The Guardian, courtesy of Lilli Heinemann

In my 20s, I studied fashion design in Berlin and then moved to London. I met people I still count among my closest friends, and found love. But, time and again, I was overcome by fear and panic. Shortly before my 30th birthday, in an attempt to understand why I felt that way, I decided to look back at my family’s past. I wanted to find out if it was possible for trauma to be passed across two generations; if the source of my inexplicable fear dates back to the night of 20 November 1945.

I knew I was breaking decades of silence within the family. I read my grandfather’s little green book, published in the 1960s and titled Forgiveness Not Vengeance; over its 40 pages, he describes in detail what happened that night. I talked to my mother and her three siblings, some of whom I hadn’t seen since I was a child. I met a good friend of my grandfather, and one of my grandmother’s sisters who I had never met. I spent days in the Bremen state archive, reading files, trawling through newspaper articles and learning the details of the brutal murders. For me, the most astounding thing was that my grandfather had forgiven the murderers and, in some cases, appealed for their life sentences to be commuted.

How do you learn to forgive a loss so catastrophic?

***

In late 1945 my grandfather, Wilhelm Hamelmann, then 43, was living with his family in the remote neighbourhood of Blockland. The flat, waterlogged land was drained by ditches and canals, and the farms were set far apart. On the evening of 20 November, my grandfather and the other residents of the farm were at home: his parents-in-law, Wilhelm and Meta Flothmeier; his parents, Heinrich and Berta Hamelmann; his wife, Margaret; their four children, Ruth, Martha, Lieschen and Willi; a visitor by the name of Beta Gerdes; the maid, Meta Howald; and the farmhand, Fritz Heitmann – 13 people in all. They spent the evening together and went to bed around 10.

Shortly before midnight – as my grandfather recounted at the trial, and later in his book – they were woken by loud noises. My grandfather got up and went into the hall, where he was approached by a group of armed men, former forced labourers from Poland. The intruders were led by a man who spoke good German; he pointed his gun at my grandfather and forced him to fetch everyone in the house. They were locked in a bedroom, under guard. The men cut the telephone line, blacked out the windows with pillows and rummaged through cupboards, drawers and chests, stealing clothing, valuables and jewellery, heaping up their spoils. Then the ringleader ordered my grandfather and the others down to the cellar.

In the cramped room, the ceiling was too low for an adult to stand upright, so they knelt on the damp floor. The ringleader and three accomplices followed them in and ordered my grandfather to swear he wouldn’t report them to the police. He declared he had no intention of reporting them. The leader loaded his gun and handed out bullets to one of the other men, who slid them into the magazine of his pistol. The ringleader stepped up to my grandfather and fired. The shot missed my grandfather’s head but hit him in the chest, entering his lung; he slumped to the ground. Everyone else was shot dead. In the subsequent trial, the number of shooters was not made clear, but it must have been at least two – the police found bullets of two different calibres. My grandfather, lying on the ground, was also hit in his left foot, his right arm and his buttocks.

Facebook Twitter Pinterest Lilli Heinemann: ‘How do you learn to forgive a loss so catastrophic?’ Photograph: Eva Tuerbl/The Guardian

After firing the last shot, the men switched off the light and left the cellar. Their leader returned three times to make sure no one was moving. The last time, he walked up to my grandfather, lifted up his uninjured right leg, pulled off the shoe and threw the leg back down on the floor. He did the same with the left leg, which was bleeding heavily from the foot. Despite the pain, my grandfather played dead until the attackers left the farm. Then, using his unharmed left arm and right leg, he crawled in the dark over the corpses of his family, up into the living room. Somehow, he managed to reach a neighbouring farm, 2km away, on a child’s bicycle – the only means of transport the men hadn’t taken. Once there, he called the police and was taken to the hospital in Bremen, where he spent the next three months recovering.

The photographs I found at the Bremen state archive in the summer of 2018 must have been taken shortly after the police arrived at the scene. I flicked through a file containing police reports and medical certificates. An envelope was stuck to the back of one autopsy report. I opened it, unsuspecting and unprepared, and took out three black-and-white photos that shocked me to the core. I couldn’t look, and I couldn’t look away. They showed the view into the cellar on the night of the murder, from three different angles. The lifeless human bodies were packed close, curled up, blood flowing from their mouths and noses and dried on their faces, nightshirts soaked in the stuff. Beside them were provisions – jars and pots of preserves, egg boxes, potatoes. I looked at the pictures knowing that if these people hadn’t died, I wouldn’t be alive today.

When I began my research I was unprepared, almost naive. I hadn’t realised it would lead to sleepless nights spent crying, not understanding why I felt so sad about the deaths of people I never knew.

***

My grandfather was a deeply religious man. Besides working as a pharmacist, he was on the governing board of a church in Bremen. During the second world war, the community was part of the Confessing Church, an opposition movement that stood against the Nazi regime from 1934 onwards, resisting the alignment of Protestantism with National Socialism.

A guiding principle of his faith was the commandment to love thy neighbour. A good friend of his – a much younger man who met him while working for the church – described him to me with a mixture of respect and admiration. “He was a crystal-clear thinker. He didn’t talk much, but what he did say had weight to it. I learned from him that you have to live with people’s weaknesses – you can and must help them to bear them.”

His second family, like his first, had three girls and a boy. Three were given the same names as his dead children

In his book, my grandfather describes how he prayed on the night of the murder, and was granted peace and strength. He details his thoughts as he left the cellar: “What kind of God allows such a thing to happen? How can you reconcile this with ‘love thy enemies’? When people have caused you immeasurable suffering, you have to demand vengeance.” He adds: “It became immediately apparent to me that the enemy had struck at my sense of reason, and if I were to lose this battle, my whole self would be lost.” And then something that many will find incomprehensible: “The Lord granted me love directly – His love – for these poor people seduced by Satan… His mercy was my mercy. His forgiveness was my forgiveness.”

The ringleader of the intruders, Zygmunt, whose surname I have been unable to find, fled that night and was never caught. Some years after the trial, my grandfather learned where he was living but never followed it up. “I don’t need to pursue him,” he wrote. “I have entrusted that poor man to my Lord. Let Him grant him mercy, that he may deliver his heart to God.”

My grandfather’s forgiveness may have been grounded in his faith, but it was also political. He saw the crime in the context of its time, understood that the young men, who had been brought to Germany and exploited as forced labourers, had experienced terrible things themselves. In an April 1967 newspaper article, my grandfather was quoted as saying: “These people had lived through difficult experiences that had filled them with hate… The leader of the gang had lost his parents in the war. The SS had shot them dead in Poland.”

Why the robbery ended in mass murder remains a mystery. The intruders had no relationship with my grandfather and his family. One of the men later said in court that he had asked Zygmunt what had happened in the cellar; he had answered “that he had finally got revenge for his family”.

Facebook Twitter Pinterest Hamelmann with a newspaper article showing the suspects in the dock in 1946. He is pointing to Czeslaw Godlewski whose release from jail he secured in 1969. Photograph: courtesy of Lilli Heinemann

Eight of the 10 suspects, all young men in their early 20s, were arrested in the Tirpitz displaced persons camp in Bremen-Gröpelingen and handed over to a US military tribunal (at the time, Bremen was part of the US occupied zone). The next day, they were presented to my grandfather, critically injured in his hospital bed. He thought he recognised them as the men from the night of the murder. The authorities, mindful of public opinion, wanted swift arrests. That they were satisfied with the hand gestures of a severely injured and traumatised victim suggests they had already decided who they wanted to see in court.

On 1 December 1945, the victims’ funeral took place at Wasserhorst cemetery in Blockland – without my grandfather, who couldn’t leave his sickbed. He asked for his words to be read aloud: “Our house was always a house of love, where the lowest found respect and the poorest found help. This shall continue to be my lodestar. Now is an especially apt time for people to begin again to appreciate and do good to one another.”

The trial began several months later. In his book, my grandfather wrote that, the day before, the public prosecutor told him he would be seeking the death penalty for all eight men. My grandfather asked him to do so only for the ringleader and the men who carried out the shootings, and to demand lesser penalties for the others.

After only three days, the judges passed sentence. The ringleader, Zygmunt, convicted in absentia, and four other men were condemned to death by firing squad. A further three received life sentences. Another was given 40 years in prison. A ninth man was arrested in Munich several months later and also sentenced to life imprisonment. The court files have been lost, so we cannot know the reasons for the different sentences. Although the murder weapons were never discovered, there was other incriminating evidence, including the fingerprints of two suspects. My grandfather could identify five defendants in court, and there were partial confessions. However, none of the suspects admitted to the murders. The four condemned men were executed on a former firing range on 13 July 1946.

Facebook Twitter Pinterest A 1967 article about Hamelmann visiting two of the convicted men in prison. Photograph: courtesy of Lilli Heinemann

My grandfather met my grandmother in hospital, where she had been caring for him as a nurse. With accommodation scarce after the war, they had no alternative but to move back into the Blockland farm. They started a family and had four children. As with my grandfather’s first family, there were three girls and one boy. The first three were given the same names as the dead children: Ruth, Elisabeth and Wilhelm. My mother was not named after the fourth murdered child. She was born much later, on 20 November 1958, the anniversary of the killings.

***

It has been two years since my mother and I began talking about that night and its legacy. In our first conversation, she tells me that everyone in the family suffered: the case was so widely known in the 60s that reporters doorstepped the family home. When I tell her I intend to publish my research, she says it is no one else’s business. We talk more over the next few months, and gradually she begins to understand.

In one of our conversations, she recalls that pictures of her father’s first family were set up on the piano on her birthday. “At some point I wondered why. But I never asked out loud,” she says. “There was an unspoken weight hanging over the household. I don’t know if it was only at that time of year, or if it was always there.”

In 1967, more than 20 years after the murders, my grandfather discovered that a journalist had spoken to three inmates of Hamburg-Fuhlsbüttel prison, Czeslaw Godlewski, Michael Strocki and Marjan Oboza. They were three of the men sentenced to life imprisonment, having been found guilty of taking part in the robbery but not the shooting. The men’s appeals for clemency had been repeatedly denied; a pardon was dependent on the men returning to Poland, but their home country refused to take them.

My grandfather decided to visit the prisoners. On 8 April 1967, he wrote, he was received by the prison director, and spoke to Godlewski and Oboza. The third inmate, Strocki, refused to talk, saying he had no interest in a pardon. The two men were brought to see my grandfather in a visiting room, one at a time. Godlewski was defensive, certain my grandfather wouldn’t be able to help him. Oboza didn’t understand why my grandfather was visiting him, and said he’d had sleepless nights. A few weeks later, my grandfather returned to the prison.

Unprocessed trauma is passed on to the next generation, revealing itself in their dreams, feelings and behaviour

In a letter dated 29 April 1967, which I found in the Bremen state archive, my grandfather wrote to the US ambassador, requesting that the two men be pardoned: “I have now visited Godlewski in Fuhlsbüttel penitentiary and told him I have forgiven him. Should he be pardoned, I hope to take him in and employ him as a janitor in a private old people’s home that I own… As the man most affected by the attack, I ask you, Your Excellency, for mercy for a man who did wrong in the confusion of an unprecedented time and who regrets. He has served 21 years. That is a very long time… Hate will only ever sow hate, and therefore it is time to stop hating once and for all.”

His appeals were heard. In December 1968, Oboza was released on probation and housed in Bielefeld, where my grandfather visited him several times. Godlewski was also pardoned in March 1969, and initially taken to a home near Hagen. My grandfather did take him in, at the retirement home he ran with my grandmother; but before long, constant anonymous threats forced him to move Godlewski to an undisclosed location.

***

In 2018, I make two visits to my aunt in her house outside Bremen. We lost touch when I was a teenager, as by then she and my mother had little contact. My aunt is in her early 70s, cautious and composed. She and my other aunt took over the retirement home after their parents’ death; my cousin is now in charge. Sitting together in her garden, I mention my research and ask for her help. We spread out all the newspaper articles and photos on a table. It feels strange to question my aunt in this way, but she is friendly and tries to answer as well as she can. She can’t tell me when she found out about the murders, or describe how they have affected her life.

But she does remember meeting Godlewski, who had been 23 when he committed the crime. At the time, she was a young adult working in her parents’ retirement home. They didn’t talk much, but he seemed reserved and friendly. More difficult than meeting Godlewski, she says, was the “terrible time” when journalists were writing about her father, the telephone ringing every day, and the family heckled on the street by strangers.

My aunt says the family stood by my grandfather’s decision; they knew that “forgiveness, not vengeance” were more than just words for him. She hands me a yellowed file labelled “Blockland correspondence”, in which my grandfather kept the many letters he received in response to his forgiveness. Many are long, handwritten missives full of admiration and appreciation. Others testify to a lack of understanding: “Your intention has nothing to do with Christianity. It is incomprehensible to everyone. Did you ever think of those cruelly murdered? How can you do this to your poor children?”

***

More than 70 years have passed since the murders. Everyone I speak to in my family is willing to talk, but I get a sense that they would prefer to let the subject lie. Time and again I hear: “We didn’t talk about it” and, “Why can’t we leave the past in peace?” I ask them about the story’s significance in their own lives. They look at me in surprise, as if they’ve never thought about it.

Facebook Twitter Pinterest Hamelmann’s book about the murders

I travel to Hamburg to meet the psychologist Sandra Konrad and ask her about what Sigmund Freud referred to as “emotional inheritance”. One of Konrad’s specialist areas is the way trauma is passed down through multiple generations. She explains that the transmission of trauma can take place on different levels: via genetics, our ties to our parents, the atmosphere in which we grow up, the stories that are told, and the stories that are left untold. Anything shrouded in silence occupies a particularly significant space. She explains that the core of a trauma lies in the inability to process terrible experiences, to overcome them by grieving, and to integrate them into our own stories. Unprocessed trauma is then passed on to the next generation, revealing itself in their dreams, feelings and behaviour.

I can’t say whether my anxiety – fears I can now live with – can be traced back to my grandfather’s experiences, other family traumas or my own experiences. But what I do recognise is that his story is part of me, just as other family stories are. Having disentangled this secret, I now have the ability to process it.

Of all my family members, I am the most distant from the event, and yet I know the most about it. Perhaps I can only dig into it because of that distance; because it’s less painful for me. Or it might be that my wish to offload this inherited burden is greater. Even as I write, I notice the weight of it becoming lighter, less threatening.

Many of my questions remain unanswered. I admire my grandfather for forgiving, but I still don’t understand how he was able to. It may be that forgiveness was a survival strategy for him, the only way he could go on living. But where was his anger? Where was his pain? And what does his refusal to permit himself these feelings mean for me?

While I may never fully understand this, I have got to know my late grandfather in other ways. I’m told he was popular everywhere, a role model for many – always cheerful, slightly chaotic and “crazy about cars”, a man who loved to drive his Borgward Isabella far too fast. In the pharmacy where he worked for many years, a painkiller was sold based on his own recipe, mixed by the whole family at the kitchen table. It is said to have been called Contra-Pain.

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