In the depths of the winter of 1605, Luisa de Carvajal, a 39-year-old Spanish noblewoman convalescing from bronchitis, began an epic journey on a mule across the frozen Pyrenees. Smuggled into England by the Jesuits, despite not speaking a word of English and being without luggage, she arrived in London shortly before the Gunpowder Plot.

Luisa (she liked to be known by her first name) is a biographer's dream. Her literary remains include 180 letters, her memoirs, and a volume almost 700 folios long containing the statements of the people who knew her. In a wholly original sequel to an earlier book on Anglo-Spanish relations in the reign of James I, Glyn Redworth, a professor of Spanish history, seizes on this material to tell Luisa's story.

Born to wealthy parents in a small hill town near the Portuguese border, Luisa was orphaned when she was six. Sent first to relatives in Madrid, and afterwards to Pamplona, where her uncle, the Marquis of Almazan, was viceroy of Navarre, she was seriously abused. Estranged from his wife (they lived in separate parts of the palace), the marquis, perhaps a sexual pervert, gave Luisa a whip for her “penitential exercises”. In clandestine sessions in his private chapel, he forced her to kneel, stripped to the waist, while a female servant administered up to 150 lashes. At midnight, he would make her put a noose around her neck and walk naked through the palace. Revealingly, he never scourged his own daughters.

At the age of 25, when she finally felt able to break free, Luisa cut off her hair, put on a veil, and set her sights on martyrdom. After first attempting, unsuccessfully, to found a new type of religious order, she gave away her fortune to the Jesuits, who sent her to England to be a missionary.

Whether Luisa made these choices quite as independently as Redworth suggests is arguable. She may have been manipulated, since the Jesuits had no qualms about sending her across the mountains in midwinter as soon as they had her money. Either way, Luisa couldn't have picked a worse moment to arrive, since the Gunpowder Plot put an end to any hope that James I would revoke the penal laws against Catholics. By 1605, England had become a confessional state in which only Protestants could sit in parliament or hold public office. Attending mass (even in private houses) was illegal. Catholic priests could be executed simply for being in the country. Amazingly, Luisa managed to survive in this hostile environment for eight years.

After learning English in the safe haven of the Spanish embassy, Luisa raised donations in Spain, then rented a house in the Barbican before moving to Spitalfields. Like most visiting Spaniards, she found London house prices exorbitant and the food tasteless. Her vignettes of neighbours in her letters are hilarious. They were, it seems, a rowdy and unhygienic lot, making horrible smells by roasting meat, and (apparently) binge-drinking on Friday nights.

Recruiting six female companions, Luisa founded “the Community of the Sovereign Virgin Mary”. Their mission was to encourage priests to defy King James's oath of allegiance, to shelter Catholics on the run, and to smuggle forbidden books into the country and people out (especially women hoping to be nuns). Redworth believes Luisa got away with this for so long because she was a woman. In a patriarchal society, females were not automatically seen as a threat. London was a cosmopolitan city full of foreigners, their wives and servants, who could go unnoticed for years. In any case, since Luisa spoke English with a thick guttural accent, everyone mistook her for a Scot.

But she created too many waves. Veiled or masked, dressed in black and sporting a crucifix, she visited London's jails, com-forting the Catholic prisoners, encouraging priests to say illegal masses for them and even hosting dinners for those about to be executed for their faith.

When she began sending male servants to dig up the mutilated, headless corpses of Catholic priests from the burial pits near Tyburn to make reliquaries, King James's patience snapped. Luisa was warned, but carried on regardless. One day while out shopping in Cheapside, she traduced the reputation of the late Queen Elizabeth and praised Mary, Queen of Scots, arousing the anger of the mob.

Luisa's house was surrounded by 50 armed men in a dawn raid. Using ladders to scale her garden walls before breaking down the doors, the royal pursuivants carted her off to prison, where she fell mortally sick. She was allowed to die at home - something of an anticlimax, since it had been her ambition to die on the gallows at Tyburn herself.

Redworth hasn't written a fully rounded biography, because his reluctance to stray too far from the primary sources cramps his style. He also tends to struggle whenever Luisa's own writings fail him. His Spanish descriptions are evocative, but his English scene-setting can be bland - except where Luisa does it for him. We learn disappointingly little of her thoughts beyond her obsession with martyrdom, and the account of her death is brief and clinical. Still, by painstakingly reconstructing her story and recounting it with gusto, Redworth has, despite all these caveats, pulled off a literary coup.

The She-Apostle by Glyn Redworth
OUP £16.99 pp288

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