The Convert by Stefan Hertmans (Harvill Secker, £14.99)

If your idea of a good holiday read is something emotionally unchallenging and mentally untaxing, then on no account pick up this book.

The flight of Vigdis Gudbrandr, a highborn Norman Christian and Jewish convert, a thousand years ago, is as demanding of the reader’s imagination as it is of his or her concentration. 

It maps her phenomenal journey from Narbonne to Nájera, by way of Italy, Sicily and Egypt, through war and pogrom, disease and starvation, at the launch of the Crusades. 

What opens as romantically as Romeo and Juliet with the love story of two young adolescents whose wealthy, partisan and influential families are implacably opposed, ends equally as drastically.

David Todros, son of France’s Chief Rabbi, takes his proselyte bride to the Provençal village of Monieux to “take refuge under the wings of the Shechinah”, out of the way of her powerful father’s search parties. 

The quotation comes from a document labelled MNYW 1096, found a century ago in a genizah at Cairo’s Ben Ezra synagogue. In Hertmans’s reading, it refers to Monieux — where he lives — at the time of a horrific massacre perpetrated during the Crusade to Jerusalem. It seeks “to inform our honourable lords of the matter of this widow the proselytess [named Sarah Hamoutal], whose husband was R. David… killed in the synagogue and two of the children taken captive”. 

It becomes the starting point of the young widow’s journey, repeatedly seeking refuge within the international Jewish community, repeatedly falling victim along the way, to ills and illness.

And that of Hertmans’s own journey as he follows in her footsteps, only to end where he began, back at home in Monieux, where the clues — and some of the keys — to rumours of a hidden mikveh, even of treasure, persist. 

Written in an often breathless, continuous present tense, Hamoutal’s experiences are visualised following Hertmans’s own groundbreaking researches. These span the southern and northern Mediterranean and both sides of the Atlantic, and the contents of the genizah now rehoused at Cambridge University Library. 

Hamoutal’s initial flight became subject to greater historical forces of feuding nations and religions. Hertmans describes stresses (insomniac nights at the computer) and setbacks (false leads and missing material) of an entirely different order, but his account is of both journeys. 

David McKay’s translation from the Flemish is as brilliant as it is frequently brutal, and intermittently lyrical. But such was the tale of doomed love in a time that gave rise to two words for holy war that resound today: “Crusade” and “Jihad”. And of the need for asylum, as vital now as then. 

Amanda Hopkinson is a writer, translator and lecturer