I spent nine months in solitary confinement with very little access to anything. Being claustrophobic, solitary was a horrific experience. After five months my family could bring me books. When the guard opened the door and handed over the books to me, I felt liberated; I could read books, they could take me to another world, and that could transform my life.

Dr Thorne by Anthony Trollope was the first book I read. The fact that a story written in the 19th century can speak to you across time and space, throwing you into another world hundreds of years later, is phenomenal. This story of power, money and politics was so captivating that while reading it, I did not take any notice of the crying and banging on the door going on in other cells.

When I finished the book, I realised there were some blank pages at the back. I had found a pen under the carpet, hidden by a previous inmate, but no paper. I started writing things in minute handwriting on those pages and spent hours plotting how to stick them together using the honey I had in the cell, so that the guards wouldn’t notice.

I also read War and Peace. My husband and I had watched the TV series together with a cup of tea on the sofa in London a couple of months before I was arrested. It wasn’t just Tolstoy’s story; the book was a vehicle to take me back to my home in London, when I was a free person.

Then I moved to the general ward where there was a community of people. It turned out we had a secret library in the ward with the majority of the books hidden in inmates’ beds. Through this hidden gem, we circulated the books between those we trusted. We were not willing to let prison control us over what we read at a time where they controlled everything else.

One day a cell-mate received a book through the post; it was the Handmaid’s Tale by Margaret Atwood, translated into Farsi. Who thought a book banned in Iran could find its way to prison through the post? We hid the cover with newspaper to avoid being caught on the camera. There was a long waiting list of inmates wanting to read the book, as well as one of the guards.

Later I read The Return by Hisham Matar; a paralysing story of a man in search of his father who has disappeared many years earlier in prisons of Gaddafi. The story was so bitter I had to drag myself to finish the book, but the name of the book kept me going; I wanted to return.

I made bookmarks while I was in Evin prison. On the front I painted a watercolour, and on the back a message: “Escape to another world.” My family sent them to friends outside, but also to those who helped us campaign. The bookmarks connected us to each other.

Books helped me to take refuge in the world of others when I was incapable of making one of my own. They salvaged me by being one of the very few tools I had, together with imagination, to escape the Evin walls without physically moving.

When we left, we all bequeathed books to the secret library in the ward to keep our stories alive for others to come, just like those who left their books for us to survive.

• This is a written version of the keynote speech Nazanin Zaghari-Ratcliffe gave at the Booker Prize 2023 winner ceremony at Old Billingsgate, London on Sunday 26 November.