The Booker-wining author of Possession was known for her voracious research. Now, 68 boxes of her notebooks, letters and diaries acquired by the British Library reveal how she assembled the raw material of her fiction

At 20, Antonia Susan Byatt was not yet sure she could write. “Do I take myself seriously as a writer?” she asked herself in her diary in September 1956. “No, I think not.”

The young Byatt – who would go on to become one of Britain’s most celebrated writers, best known for her 1990 novel Possession: A Romance – was troubled by the possibility that her mind might not be equal to her ambitions. Yet her determination was already evident. On her 20th birthday, she wrote: “Today, I know I can do anything. But not yet.”