In 1962, my mother, Jolanta, wrote a memoir in her native Warsaw which she has just translated into English for me to read. Her profoundly troubling words have moved me ineffably, and reminded me forcefully how much her Jewish identity has shaped mine.

She wrote: “I was born with two sins. My christening freed me from my original sin, but I drag the second one with me to this day. I am Jewish. Not even completely Jewish because my father was Polish. But my mother was Jewish. And this is what many Poles, including many practising Catholics, cannot forgive me.”

My grandmother, her mother Barbara Lewenkopf, died of breast cancer at the age of 26 when her only child was six months old. In dying you could say she gave my mother the gift of life a second time. Without a Jewish parent in the frame, Mum’s ethnicity was easier to conceal and she spent some of World War Two hidden in a convent. The rest of the Lewenkopf family, bar one of my grandmother’s sisters who made aliyah in 1933, was murdered in the Holocaust.

I suppose the young Jolanta’s Catholic education began in that convent for her father was not a religious man. And if he did have a belief system, cruelty was central to it for once his Jewish child was back in his life, having been collected from the nuns by his non-Jewish wife, he despised his daughter thereafter. This was so obvious that on one occasion fellow residents in the apartment block opposite the Sejm, the Polish parliament, threatened to report him to the authorities. He scared them into dropping the idea.

In recent months, Mum has come to the view that her Jewishness was the likely explanation for her father’s hatred. For it was not that he was incapable of parental feeling; he was demonstrably fond of his third wife’s daughter, the step-sister with whom my mother was raised in the two-room flat in Wiejska Street.

At the very least my grandfather who died, and not a day too soon, when Mum was 16, was certainly a casual antisemite. She remembers him mocking the Yiddish inflections of his former in-laws’ Polish and recounting, with mirth, how it was fine to ride a Jewish horse, but you should take care not to fall off it.

When she wrote the above words my mother was a devout Catholic. These days, she describes herself as an agnostic and is vocally critical of the Catholic Church, although she always speaks very kindly of The Sisters of the Immaculate Conception of the Blessed Virgin Mary, who endangered their lives to save hers.

I, meanwhile, am a proud Jew, a dyed-in-the-wool atheist and a staunch Zionist. For me, the three things are interwoven branches of the same tree and are central to what makes me tick. Put another way, I find it blindingly obvious that after centuries of unspeakable oppression, Jews should seek sanctuary in a country where their ties stretch across millennia. And learning about my mother’s unhappy youth in Poland, a country of which one Israeli prime minister pointedly that said its children suck up antisemitism with their mothers’ milk, has been fundamental in bringing me to this view.

Yes, of course there were, and still are, righteous gentiles in Poland. My own mother owes her life to Polish nuns, and Yad Vashem has recognised 6,706 Poles for such acts of heroism — more than any other country. But many — perhaps most — were and remain haters of the Jewish people.

A few paragraphs on in Mum’s text, she writes: “I have a friend who having found out that her friend was Jewish broke off all relations to him. She likes me very much. Maybe my race is not so evident from my face.”

Later, she quotes extracts from readers’ letters published in a popular weekly magazine of the day called Cultural Review: “Jews out of Poland! The whole nation agrees! We will deal with them like Hitler. Because it was God himself who sent Hitler. There will come a time when not one Yid will be left alive.”

“It is difficult to say how I feel reading these words,” she writes. “I was born in Poland. I have never felt different from those around me. Shouldn’t I be judged, like everyone else, by my deeds, feelings, thoughts and desires?”

Further on, she narrates how she was invited to spend Christmas Eve, or, as she put it, “your holy day, Lord Jesus”, with a family who had always been very kind to her, “moved I think that I had been managing on my own for some years.”

The evening started well: “We laughed, we sang carols and enjoyed ourselves.” But then the conversation turned to the subject she always dreaded: Jews. “They said that in the camps, Poles had gone to their deaths with their heads held high, but the Jews, true to form, were ready to send their mothers and fathers to the ovens, just to save their own skin. They have no hearts, no conscience, no soul.”

“I searched nervously in my bag for a handkerchief, my pretend cold just a pretext to lower my head. I wanted to say something about Janusz Korczak (the Polish-Jewish educator who refused to abandon the orphaned children under his care, choosing instead to accompany them to Treblinka and die with them) but I couldn’t, I felt my face burning. What if they guessed why?”

What if they guessed why… My mother spent her Warsaw youth in a constant state of anxiety that the truth would out; that people would guess from her dark non-Slavic looks, from her mannerisms even, that she was Jewish; that when, on occasion, she was able to summon the courage to respond to an antisemitic remark, people would guess that her reason for doing so was personal.

Her fears were well founded. Of the small number of people who knew she was Jewish some would, when expedient, use it to slur her integrity. “Shut up you Jewish dog,” her friend’s boyfriend yelled when, aged 17, she asked him to return money he owed her. Sometimes, complete strangers beat her with the same stick. “I’d also look Jewish if I had a face like that!” an old, crazed man screamed at her apropos nothing at a bus stop one freezing Warsaw morning.

Some years later, Mum would write: “Lord Jesus, please come down to Earth again and say that Jews are people too, and that if they sometimes behave badly, it is not because they are Jews but because they are people. And judge them as you judge everyone else, exempt them from the responsibility of that for which they are not guilty: their race.”

My worldview today could hardly be more different than my mother’s was in 1962. I am a Jewish atheist, humanist and universalist. She was a practising Catholic who talked to God as if he were a firm but fair school chaplain.

But despite these differences her story has shaped me enormously, and helped me understand myself in ways she might only realise when she reads this article.

Because my mother lived in justifiable fear of being outed as a Jew, I always tell people I’m Jewish. Even when it would be easier not to, when it would be easier to blend in. When I was small she would tell me to make sure people liked me, that I had made a positive impression, before I revealed my identity. That’s the entirely understandable emotional response of someone who has internalised other people’s hatred. Me, I don’t need or want people to like me in spite of who I am.

Her story has also made understand the importance of community. Antisemitism is always difficult to manage, but how much harder when you have to do so entirely alone, when there is no one to advise you, to comfort you, to tell you that they know how you feel. This was my mother’s story: in all her time in Poland she never knowingly met a fellow Jew. Though she must have surely encountered secret Jews like her: Polish marranos. It is one reason I left my native South Wales for north London: through her bitter experience I learned, inversely, how communal life can bolster a positive Jewish identity.

Mum’s formative years have also made me hypervigilant to Jew-hatred in all its varied and constantly mutating forms. Although I am always ready to educate the ignorant, when I meet a dyed-in-the-wool antisemite, I feel it in my bones. I can always differentiate between legitimate criticism of Israel and those who embrace anti-Zionism for convenience, who use it as an opportunity to politicise their bile. And because it was so difficult for my mother to call out classic antisemitic prejudice, the kind that of Jew-hatred that is now politically incorrect, I try to call out dislike of Jews in all its guises. There have been times when I have failed, and my silence still fills me with shame. For unlike Mum, I am fortunate to live in a free society.

“I am Jewish. Not even completely Jewish because my father was Polish,” wrote my mother. Well, it’s certainly another take on Orthodox interpretations of halachah! But the truth is that when I was growing up I got used to hearing Mum describe herself as half-Jewish, and even then it made me wince. Half-Jewish? What’s the other half then? You either identify as Jewish or you do not.

I feel huge sorrow and huge anger at what my mother had to endure for simply for being who she was. I wish I could have been there to stand up for her, to protect her. And I also feel tremendously grateful that 57 years after those words spilled from her pen, she has shared her pain not only with her intimates but with the strangers reading this article. Her testimony will in perpetuity tell people what it was like to be Jewish in Poland after the Holocaust.