Constant’s attitude towards women was deplorable. He initially threatened — and half-heartedly attempted — to commit suicide if Mme de Staël did not become his mistress, yet within two years was finding her burdensome. As he put it in his roman à clef, Adolphe: “She was no longer an aim: she had become a tie.” Marriage to a docile, submissive wife, rather than an affair with a tempestuous ­female writer, he decided, was the best solution for his personal life. Eventually, in 1808, he found and married a suitable candidate — though he did not dare to tell Mme de Staël for another year. In a splendid example of poetic justice, Constant’s hopes of marital bliss were soon disappointed. By 1812, he was writing in his diary: “I got married in order to sleep with my wife a good deal and go to bed early. I never sleep with her, or hardly ever, and we stay up until 4 o’clock in the morning.”

Winegarten generally does justice to the remarkable partnership between Constant and Mme de Staël. She emphasises that despite its ultimate failure, it left as its monument a series of books that have enriched ­European politics and culture for the last two centuries. Above all, in an age dominated by reactionaries, dictators and demagogues, Mme de Staël and Constant helped lay the foundations of modern liberalism.