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In September 2006, in a near-empty church in Ravenna, in north-east Italy, I found myself in front of a vibrant, 1,500-year-old mosaic of a woman in purple. She had a halo, her own courtiers, and was taking up an enormous space beside a mosaic of Christ. I knew she had to matter. At the gift shop, I bought the booklet about her, which took five minutes to read. The woman was the empress Theodora and although I had never seen her before, she has come to dominate my working life
Theodora lived in an era of huge changes in the church, language and statehood. What had been Roman was about to become Byzantine, and the eastern regions around Syria, the Levant and Egypt were clamouring to use their own languages, hinting at self-determination. Just 20 years after Theodora's death the Prophet Muhammad would be born.
Despite the huge amount of history written about the period, Theodora was largely overlooked. In Procopius's Secret History, which current studies believe was written not long after her death in 548, she is a kind of Mrs Machiavelli. He calls her "Theodora-from-the-Brothel", lasciviously details her antics on stage – from allowing geese to peck grain from her lower torso, to dancing naked but for a ribbon – and has her saying she regrets God gave her only three orifices for pleasure. When he goes on to describe her husband, the emperor Justinian, as a headless demon, we can assume not everything he wrote was utter truth.
Procopius's view on Theodora, which was not published until the 17th century, certainly influenced later writers, yet she remains an enigma. What we do know about her seems fascinating, often highly modern, apparently feminist, and almost always controversial. The more I read, the more I realised she was an ideal candidate for fiction, and for the last three years I have been writing a novel about her. She was born to the bear-keeper of Constantinople's hippodrome in about AD500. Her father died when she was five and her mother married another animal-keeper. When he failed to land her dead husband's job, she rehearsed her three little girls in arm movements and the silent gestures of supplication that would have been recognized by theatre audiences of the time. Then, she dressed them up and took them to the hippodrome – a vast complex, housing a capacity crowd of 30,000 men – to formally request a job for their new stepfather. The wish was granted and Theodora went on to become an actress, dancer, mime artist, comedian.