The first instalment in The Sunsurge Quartet, Empress of the Fall takes place in the same mythological land as The Moontide Quartet. He wanted to explore "a kind of East-meets-West culture clash in a world that closely resembles ours," so Urte is divided into two distinct continents: the cold and wet Yuros, whose people are pale-skinned, and the mostly arid, equatorial Ahmedhassa, whose inhabitants have darker skin.
"Some people have asked why I didn't make it more distinctly different with different races or species of human beings," says Hair, who crucially chose not to include any elves, dwarfs or similar mythical creatures.
It felt false to do that, he says, because he wanted to write something that said something about our world as well as being an escapist fantasy. It can be read by people who just want to read it purely as a fantasy but it also has some reflections that will hopefully make readers curious about what happened in the Crusades or other events of history.
As he spent 10 years completing a part-time BA in History and Classical Studies while holding down jobs at the Bank of New Zealand and various insurance companies, Hair's academic and professional achievements have also impacted on his novels.
"I was in marketing and had to write a lot of investment commentaries, so I've always tried to see the whole picture of something," he says. "That means not only are you looking at the personalities and personal lives of your characters, you're also looking at the bigger picture in terms of military and the economics of the time and you've also got the philosophies and beliefs of the culture as well."
Given this, Hair was determined to make his invented realm as recognisable as possible.
"It's such a hefty story already that I didn't want to make it another 30 per cent longer by having to describe cultures that people have never experienced.
"I deliberately used real-world terms, like saris and bindis, so that people would read them and know what they meant. I wanted the reading experience to be as instinctive and streamlined as possible. I wanted to provide a context for people to think about, such as where they stand on the clash between East and West."
Comparing her to a character out of a fairytale, Empress of the Fall centres around Lyra Vereinen, who ascends to the throne of Yuros on the death of her uncle, the Emperor Constant.
Hair describes Lyra as having a kind of Sleeping Beauty element because she's been plucked from a dreamlike existence in a convent and suddenly must deal with the real world "in all its glory".
"It's about what happens when somebody, who many would say is unsuited to being placed in a role of leadership, has it thrust upon them by circumstance and then has to cope with the situation and with other people's ambitions."
Although Urte has no direct link to his homeland, Hair believes coming from New Zealand has impacted on his writing.
"It has that Kiwi outlook of what's fair play, getting a balanced approach to a problem and trying to see both sides of an argument. We see ourselves as geopolitically quasi-neutral about a lot of things and that kind of attitude perhaps comes through in the story.
"In Empress of the Fall, I've tried to be even-handed, so there are villains on both sides. I guess it's about the struggle between good and evil, which is spread pretty evenly over the East and the West, rather than condemning one particular side. "That's the Kiwi way."
The Sunsurge Quartet: Empress of the Fall
by David Hair
(Hachette, $30)