M.L. Stedman’s debut novel, The Light Between Oceans, puts a young couple on a remote island off the coast of Australia after WWI—and tests the limits of motherhood.

You’ve set up a unique situation that allows for questions on the nature of motherhood to arise naturally. What came first when conceptualizing the story: the moral dilemma, the setting on Janus Rock, or the historical moment in time?

I write very instinctively, letting a picture or phrase or voice come into my mind, and following where it leads. The setting turned up first—I closed my eyes and saw a lighthouse, then gradually a woman, and I knew it was a long time ago, on an island off western Australia. Then a man appeared—the lightkeeper. As I wrote, a boat washed up, with a dead body and a crying baby, so I had to keep writing to see what happened. I didn’t know who these people were, and it was only as I continued that the moral dilemma emerged.

Different characters in the book have very clear but opposing views as to what is the right thing to do with the baby. Did you yourself struggle with the end result, or was it clear to you from the beginning?

I had no idea how the story would end until it ended: it really could have gone any way. That means readers, too, say they can’t guess the end. I loved having complete freedom to see where it wanted to go—I didn’t have to arrive at a given destination, so I didn’t have to contrive a way of getting there.

How long did you work on the novel?

The book itself didn’t take a vast amount of time—it began in 2008. But I started writing fiction, finding my way with words, back in 1997. I’d always written short stories, because novels seemed massively daunting—like the difference between building a sand castle and a cathedral. I sort of tricked myself into making the leap, because I didn’t know The Light Between Oceans was a novel at first. It was just two people and a lighthouse, in the middle of nowhere.

There are many details surrounding life as a lighthouse keeper in post-WWI Australia and the mechanics of the light itself. What was your research process like?

My research process was like heaven—I loved every minute of it. Lighthouses are very addictive (reader, beware!), and their history is simply fascinating. As well as reading about them, I climbed up them, inspected lenses, and scoured old log books in the Australian National Archives, as well as lightkeepers’ correspondence: still voices, still resonating silently in the pages. I also researched western Australia’s role in WWI and spent time in the British Library reading battalion histories and other materials, frequently in tears at letters home from boys, or stories of fallen comrades told plainly by those who survived. Australia’s war records are beautifully maintained, and there’s something bittersweet in the surgical precision with which these documents, which are ultimately a story of chaos, have been kept, and now digitized.

What are you working on now?

This book is still taking up most of my time. Once things quieten down a little, I’ll close my eyes again, and see what turns up.