Barbara Kingsolver has never ducked the big questions in her fiction. ‘I don’t understand how any good art could fail to be political,’ she told an interviewer in 2010 after her sixth novel, The Lacuna, scooped the Orange Prize. In 2000 she established the Bellwether Prize for Socially Engaged Fiction, awarded to an unpublished novel that addresses issues of social justice. As well as a big cheque, the winner receives a publishing contract.

Overtly political agendas can sometimes turn novels into preachy polemics, but Kingsolver’s finest books demonstrate the extraordinary power of a fierce morality when harnessed to formidable literary skill. The Poisonwood Bible memorably tackled the dark history of colonialism in Africa; The Lacuna probed censorship in McCarthyite America; Flight Behaviour examined