When I was a child, my brother, Jaanus, and I would always get excited about the summer holidays because we knew we were going to stay with our grandparents. We lived in Estonia’s capital, Tallinn, and they had a small summer house near the village of Kabli on a beautiful stretch of the Estonian coastline. It was surrounded by pine forests and close to wonderful beaches where we’d swim and play games for hours. It was idyllic.

Inside the house, my grandmother spent a lot of time in the kitchen pickling and preserving — onions, eels, tomatoes, gherkins, all sorts. We’d get up in the morning to find pots boiling on the stove and vinegars, oils and spices on the table. Meanwhile, Grandfather picked blackberries and wild strawberries for us to have with our porridge.

It was one such holiday. I was 10; my brother was 14. What made it stand out were the constant TV clips of Estonian politicians demanding independence from the Soviet Union, which was finally declared on August 20, 1991. I was still too young to understand the importance of that day in our history, but the following day I was to get a strong sense of what it meant to my grandmother. I was outside with Jaanus when we heard this strange rumbling noise. It was coming from the highway — a few metres away. We ran inside to tell my grandmother, who came to the gate.

Without saying a word, she ushered us back in and bolted the door. She and my grandfather locked windows, closed curtains and put out fires. We asked her what the noise was. She just smiled reassuringly and said we were going to play a game — we were going to pretend nobody was in the house. We followed our grandparents down to the basement. Now the noise was deafening. The walls shook. The furniture rattled.

My grandmother seemed calm, but she knew all too well it was the sound of Soviet tanks, a sound she’d first heard as a girl, living on the Estonian island of Saaremaa. It was June 1940 and Stalin’s Red Army had just invaded. Thousands of Estonians were sent to Siberian labour camps, and for the rest of the second world war Estonia was occupied by either the Russians or the Germans.

When the war ended, Estonians hoped their freedom would return, but in 1949 Stalin instigated a new reign of terror. Fearing a repeat of the deportations in the war, many Estonians tried to escape on ships going to Sweden or Canada. My grandmother, who’d married the year before and had a baby, tried leaving with her husband, but they couldn’t get out on the same ship. She insisted he go first and she’d follow the next day. She never made it. The Red Army were quick to tighten their grip. Dissidents were killed and with new quotas to fill for labour camps, troops went from house to house, often taking entire families.

The day they came to Grandmother’s house, she was out, but she returned to find her parents and her sister had been taken. She fled with her baby into nearby forests. In the middle of the night she reached a lodge where the forester and his wife said the troops had let them stay. She knew she couldn’t take refuge there, but she begged them to take her baby. They agreed, and she escaped back into the forest. But troops tracked her down and she was sent to the island’s prison. There, she was beaten constantly. It’s a miracle she survived. Weeks passed, she was weak and grief-stricken. Then she heard some prisoners were planning an escape. To be caught meant execution, but she knew it might be her only chance of getting out alive.

Amazingly, they all got out and my grandmother went back and got her baby. She escaped deportation, but she never saw her parents and sister again. They perished in the labour camps. As for her husband, he reached Canada, but could never return. Her life was in pieces, but eventually she remarried — to the grandfather I knew — and she then had another child: my father.

Before that day in 1991, she had never spoken to me of her suffering. But as we sat in the basement, she did talk; bit by bit. We remained down there until nightfall, long after the sounds of the tanks had disappeared. There were no phones then, so we couldn’t contact anyone. Only that night, when we watched the news, did we learn that Soviet tanks had rolled into the capital and tried to retake control. Thankfully, they failed, and Estonians kept their freedom. During that period, the other Baltic States, Latvia and Lithuania, also won their independence. And four months later, the USSR was dissolved.

Sadly, my grandparents are no longer with us, but every year I return to the summer house and I think about that day… a day I shall never forget.

To mark the 90th anniversary of the Republic of Estonia, Hannah is singing at St Paul’s, Knightsbridge, London SW1, on July 8. Visit www.hannahsite.com

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