Shepard’s new novel, The Book of Aron, locates itself at the centre of one of the most extreme places in history: the Warsaw ghetto under the Nazis. It takes up the story of Janusz Korczak, the Jewish doctor and educational reformer who set up an orphanage inside the walls of the Jewish ghetto. Importantly for Shepard, however, Korczak is not the novel’s protagonist, but rather a secondary figure. The protagonist is the eponymous Aron, a child who learns to live by his wits – smuggling, colluding, and doing pretty much anything he has to in order to survive – before winding up in the care of the saintly Korczak.

“I was dealing with the kind of figure that normally doesn’t get narrated,” Shepard says of his approach to the novel. “One of the insidious things about a lot of Holocaust narratives is the way they choose figures that are quite extraordinary.”

Shepard cites Thomas Keneally’s novel Schindler’s List and The Diary of Anne Frank as books that fall into this category, and offers a tacit rebuke to critics such as Geraldine Brooks, whose recent New York Times review of The Book of Aron questioned why the story wasn’t narrated from Korczak’s perspective. Reading Frank’s diary, Shepard posits, it’s impossible not to be astounded by the intelligence and empathic rumination that infuses the writing of such a young girl. “And it’s one short step from that to, you know, the Holocaust was a terrible thing because it killed Anne Frank,” Shepard says. “I thought, what about those people nobody valued, what about those people who got swept away. And, you know, all those people in the background of all the newsreels. I very much like that worm’s eye view, that sense that nobody cares about my protagonist but me.”

Brooks also points out that in order for Shepard to inhabit Aron’s consciousness, he must forgo numerous writerly flourishes, such as lush vocabulary and metaphor. She suggests this is a risky proposition for an author, but it is in fact simply another characteristic of Shepard’s writing. For all its diversity in terms of subject, Shepard’s fiction – be it novels or stories – is notable for its concision, its ruthless paring away of anything extraneous. “I’m really attracted to leanness,” Shepard says, while at the same time acknowledging, “I don’t think that’s a mainstream, readerly pleasure.”

Shepard suggests that Anthony Doerr’s Pulitzer Prize winner, All the Light We Cannot See, offers an example of a book that resides at the other end of the spectrum from The Book of Aron. “Tony’s book is 500, 600 pages, and it reads pretty quickly, and readers feel like, I got my money’s worth there. [Whereas] mine is a shuttered, streamlined little thing.”

While Shepard’s attachment to sparseness is apparently engrained in his makeup, he is cognizant of the mainstream limitations inherent in this approach. “I recognize that in fact it’s not what I would call a good business decision,” he says. “I think the big canvas not only attracts more readers, but it feels self-consciously more important. It’s big in both senses of the word.”

And though it would be difficult to deny the evident ambition in Shepard’s range of output and his ability to inhabit an apparently endless variety of different characters convincingly, this is not the kind of ambition that calls attention to itself and wins prizes. “I’d be miserable if I didn’t think my work was ambitious,” Shepard says. “I think my work is extraordinarily ambitious, but I think you have to be a certain kind of reader to understand that. When you get a 700-page novel that is explicitly talking about the rights of man, even falling down the stairs you would think this is an ambitious book. So, it’s much more signposted.”