In Black Sun Rising (Pegasus Crime, June.), a British PI investigates a complex mystery in 1909 Barcelona involving terrorists and eugenics.

How did this book come to be?

I’ve always been interested in the combination of rational and irrational forces that can lead societies to collapse and implode. Ever since I first read about the clash between the Spanish army and anarchists in the urban insurrection known as Tragic Week, this curious historical event offered an ideal opportunity to explore these possibilities. Over the years, I’ve considered various possible fictional scenarios, using Tragic Week as a background. It was only recently that I began to see this as an opportunity to bring in wider themes relevant to a 21st-century readership.

What precedents for today’s political trends that feature in your novel came from this period?

Nowadays we often hear comparisons between contemporary populist politics and the 1930s, but many of the intellectual attitudes and social/cultural forces that led to fascism were already embedded in European society in the years before WWI. Bearing in mind that history never repeats itself exactly, the “great replacement” theory propagated by the contemporary alt-right and the degeneration and decline narratives that underpin the new 21st-century nationalist populism were all present back then.

In what significant ways did the thinking of people in 1909, both in England and Continental Europe, differ from contemporary mainstream thought?

The people of 1909 lived at a time of rampant militarism and nationalist competition, in which war was seen as a glorious activity and a defining hallmark of national “virility” and individual manhood. Racism, social Darwinism, eugenics, racial pseudoscience, and aggressive nationalism all enjoyed widespread intellectual and social credibility and respectability. In the last few years, we’ve witnessed insidious attempts to make racism and nationalism acceptable once again. Given these developments, I hope my novel can help to remind readers where these tendencies can lead.

Does this book share themes with your previous historical mystery?

The Devils of Cardona dealt with an early period in Spanish history and in the history of racism, in which religion and culture, rather than skin color or biology were seen as the markers of inferiority and superiority in establishing which Spaniards possessed “purity of blood.” Black Sun Rising takes place at a time when racism was justified through science and pseudo-science, myth and superstition. Both explore what happens when societies act against imagined and imaginary monsters without realizing that the most dangerous monsters are often already present inside them.