According to a new study of his time in Provence, the gruesome procedure was in fact inspired by the news his brother Theo, his most loyal confidant and financial supporter, was about to marry after a whirlwind romance. The research throws doubt on the popular theory that Van Gogh took a razor to his ear after a passionate row with fellow artist Paul Gauguin.

It was known that Van Gogh was distressed by news of the marriage – which could have threatened the closeness of their relationship, and also left Theo with a wife and family to support, unable to fund a struggling brother who had yet to sell a single canvas – but it had been thought that he learned of it only after the incident.

However, the writer Martin Bailey, for his new book Studio of the South, has uncovered evidence that Van Gogh almost certainly learned of it in a letter from Theo delivered on Sunday 23 December 1888.

Later that night there was indeed a quarrel, after the two artists had spent the day working penned up together by continuous rain, and Gauguin would leave the house threatening to return to Paris – but the trigger for Van Gogh’s despair was not that, but the news from his brother, Bailey believes.

Theo’s letter enclosed 100 francs, but also the news that only a fortnight earlier he had met an old friend, Jo Bonger, who had previously turned him down. This time, within a week, she had agreed to marry him.