The spark that ignited Markus Zusak’s much anticipated latest book arrived in 1995 – a full decade before the publication of The Book Thief, the novel that would make him a literary superstar.

“I was 20 years old when I first thought of a boy building a bridge, and wanting to make one beautiful and perfect thing,” the author of the newly-released Bridge of Clay tells The New Daily.

“I named the protagonist Clayton. It was originally called Clayton’s Bridge, and then a few months later, I thought ‘No, make it Bridge of Clay’,” Zusak, 43, says.

“I thought, ‘that’s it – the bridge will be made of him – of everything inside him’.”

The 13-year process of writing the multi-generational family saga about five brothers growing up amid grief and abandonment took its toll on the author, who in 2014 gave a TEDx Talk on the benefits of failure.

During the struggle to bring his latest work to the page, Zusak described himself as a “a different person” to the one who began it, but now he’s rediscovered himself.

“I feel more like the person I’ve always been, who loves writing and stories … It’s amazing how different you feel when you’ve made it to the other side again.”

Like his protagonist, Zusak is from a big family, something he explores in his new novel. Family, he says, is not easily defined.

“I think it’s just something we all live,” reflects Zusak, whose parents are from Germany and Austria. “What I’m interested in is the idea that who we are starts long before we’re even born … the past never quite goes away. It’s a part of who we are.”

His own memories of being the youngest of four siblings growing up in the southern Sydney suburb of Engadine, where his parents still live, are of “chaos, and arguments, but also a lot of laughter”, says Zusak, who was 16 when he began writing.

“My favourite memory was of surfing my first ever proper wave, and my brother standing on the shore, arms raised in triumph, and cheering for me. I look back and realise that moment is actually a proof of love.”

Occasionally, “a piece of Europe” would pierce the sun and saltwater of Zusak’s Australian childhood: these stories of WWII handed down by his parents went on to inspire The Book Thief, an international bestseller translated into more than 40 languages. That level of success “defines your writing career, but you can’t let it define yourself”, says Zusak.

“Mostly, I’ve felt lucky. I remember when it came out – I couldn’t imagine anyone reading it.

“To me, I’m always trying to look forward, but of course, I take that book with me. I’m really grateful to it, because, in its own small way, it’s always had a sort of charmed and magical life – and I’m so grateful to the readers who’ve embraced it the way they have. As I often say, readers owe me nothing – I owe readers everything.”

With Bridge of Clay finally delivered into their hands, its author is now keen to put his pen down and feet up over summer.

“It’s been one of those years – hectic at times, but all for good reasons,” says Zusak, who lives with wife Dominika and their two children in Sydney’s eastern suburbs. “I’m looking forward to just going to the beach with my family, and surfing with the kids. What more can you ask for in a life?”

Bridge of Clay, by Markus Zusak, Pan Macmillan, RRP$32.99