About a third of the way through Journal of a Man Unknown, the final work by the late novelist and historian Gillian Tindall, the narrator, a 17th-century ironworker named Tom Harthurst, receives a letter that changes the way he sees the world. After a brief adventure in London, Tom is back in the Sussex Weald, where he was born. He is living through a time of convulsive historical change – he was seven when the news of Charles I’s beheading reached the forest, and a bit older when he heard that a dotty old woman he knew had been drowned for being a witch – but the tremors of the age don’t seem to have shaken anything loose in Sussex just yet. Tom has a nice life, he thinks. He is esteemed by his neighbours and friends, his work is valued, he loves his wife and child and they love him back. His ‘vision and hopes’ are not ‘vested in the wider world’, and it’s only sometimes, very early in the morning, when this feels like something other than a blessing, when he wakes up and asks himself, ‘What, in truth, am I doing here?’

The letter comes from John Graunt, the historical figure now regarded as one of the founders of demography, whom Tom met in London. Graunt is writing to explain the reason for his conversion to Catholicism, a decision that baffles Tom, who has grown up thinking of Catholics as ‘basely attached to magic ideas’ and whose mother, even though she could barely read, would turn the pages of Foxe’s Book of Martyrs and ‘tut over the horrors committed by Papists therein depicted’. Beauty is the reason, Graunt says, describing the ‘heart-lifting’ vestments worn by the priests and lamenting the destruction of buildings, artworks and records in England. He asks Tom if he has come across the term ‘Antiquary’, and ends his letter with a quotation from William Dugdale, ‘who has written much on our ruined monasteries’: ‘Man without learning, and the remembrance of things past, falls into a beastly sottishness, and his life is no better to be accounted for than to be buried alive.’ With remarkable patience, Tindall shows how an idea expressed so stridently and uncompromisingly might shape the perception and life of an ordinary person.

The novel takes the form of a memoir that Tom is writing towards the end of his life, in 1708, looking back at a period which, as Tindall writes in her afterword, ‘turned out to be, in its disjointed and troubled way, a time of great promise, the hinge between