THROUGH the window of Diana Gabaldon’s Edinburgh hotel suite is a panoramic view of Arthur’s Seat, but she doesn’t need to gaze upon it and commit it to memory. Scotland’s landscapes already provide the backdrop to her multi-dimensional Outlander universe, the literary phenomenon that began as nothing more than a practice novel.

Sitting on a chintzy sofa, her boho blouse is more Arizona than Ardnamurchan, and her choice of whistle-wetter isn’t whisky, Irn-Bru or even water that tumbled from a clear Highland stream. It’s Diet Coke, straight from the bottle.

Gabaldon might be here to receive an International Contribution to Scottish Tourism award from VisitScotland, but there’s a refreshing absence of misty-eyed sentimentality when she talks about Scotland.

She doesn’t need to win us over – the numbers speak for themselves.

VisitScotland’s Outlander Effect And Tourism paper showed that attractions used in the television adaptation of the novels (eight and counting) saw numbers rise by 67% between 2013 and 2017, from 887,000 to 1.5 million. So whatever Scotland has given her in terms of literary muse, she has repaid with hotel nights and ticket sales.

READ MORE: A-Z of Outlander: Everything you need to know about the hit TV show

As with many cultural behemoths, Outlander began small. Dr Gabaldon, a university professor with degrees in Zoology and Marine Biology and a PhD in Quantitative Behavioural Ecology, was thinking about writing a novel.

Having no problems putting several thousand words together, she decided to have a bit of a practice before embarking on the real thing. She was drawn to historical fiction, but when and where should she set it?

Enter Frazer Hines in a kilt. PBS America was showing episodes of Doctor Who, as far back as Patrick Troughton episodes from the 1960s, when the time-travelling companion was Jamie McCrimmon, a piper played by Hines who meets the Time Lord in the aftermath of Culloden.

With her interest piqued and some subsequent research, it seemed Scotland in the 18th century could offer the turbulent times required for the conflict that every novel needs.

Gabaldon’s only previous brush with Scottish culture was writing comic books for Walt Disney and tackling the character of Scrooge McDuck.

“When I was growing up in Flagstaff, Arizona, Scotland wasn’t on my radar – at all,” she says. “There was nothing remotely Scottish and my family didn’t have Scottish heritage. I didn’t even see Brigadoon!”

So the first Outlander novel was created among the cacti, in the searing heat of the desert.

The story begins just after the Second World War, when an army nurse called Claire Randall is on honeymoon in the Highlands, but after touching a standing stone falls through time and into 1743. With no escape, she marries a warrior called Jamie Fraser. That’s the short version. With the ninth book due to be released this year and a series of offshoot novels and anthologies, this is a sprawling tale that, in contemporary usage, could be described as a Scottish saga and goes far beyond Gabaldon’s description of it as “big fat historical fiction”.

She adds that she made the character of Claire an Englishwoman as a way of adding to that conflict, so maybe she knew more than she was letting on… The first Outlander book was written in the late 1980s, from library research and tapping into advice from friends overseas, thanks to the embryonic online communication tools such as CompuServe.

“My friend David Stanley in Edinburgh pointed me towards Scottish authors that I should read. Believe it or not the first I read was Irvine Welsh, which is probably as far from my writing as you can get.

“I had been reading mysteries and crime novels for years, so I was particularly attracted to police procedurals and this led me to Rebus and Ian Rankin. There’s a bookstore called The Poison Pen in Scottsdale, where I live now. I would go in and ask if he had anything by Ian Rankin, and they’d say, “No, we’ve never heard of him”. And I would say: “Well, you should!” We ordered those and many other books. I think the owner became intrigued as to why I was reading Scottish authors across almost every genre.”

She would study Scottish characters on television and made a point of listening to Scottish traditional music. “I chose live recordings of bands, to hear the chat between songs. I would also source older traditional music, particularly the ballads, as I was dealing with Scotland in the 18th century.

“When I decided to ‘work’ in Scotland, if you can say that, I drove down to Phoenix because there was a Highland Games. It gave me a bit of an insight into that part of the culture and I walked around, just listening. If I heard someone who was actually Scottish I would head straight for them and ask if we could just chat”

The “practice book” became the real thing – and a successful thing at that. It was only when the second book was being written that Diana and her husband Douglas thought they should visit this faraway land that had become such a massive part of their lives.

“We had flown to London and driven north. We came over the Border at Carter Bar and I stood at the monolith that says England on one side and Scotland on the other. When I came around to the Scotland side and looked over the landscape, it was green and rolling and familiar and it really did feel like home.”

The second book was to feature Edinburgh quite heavily, but arriving in August meant there was no room at any of the inns. “We ended up staying in Dundee,” she says, “and drove back and forward every day. I suppose the distances we cover in the US can be so huge that it wasn’t too much of a struggle. You know what they say, ‘To an Englishman 100 miles is a long way but to an American 100 years is a long time’.”

She doesn’t mention whether Dundonian was unintelligible, perhaps being polite as she had asked where I was from, but she recalls trying to find a meal late at night in the city – not the easiest thing to do in the early 1990s.

“The waitress told us that they were technically closed, but supposed she could find us something. We said and said apologetically, ‘You can tell we’re Americans,’ and she said, ‘Aye. Well I suppose I’ll just have to let you aff then’.”

The first trip was more than a sightseeing holiday and a chance to research locations. The people were key to the books – the characters of course, but also the speech patterns, something that Gabaldon was determined to get right.

“I got a chance to get to grips with the actual sentence structure, which is so different in Scots than it is in straight English.

“Whatever the academic disputes about whether Scots is its own language, I see that as irrelevant for the books. I try, as far as I can, to depict Scottish speech as correctly as I possibly can, to make it understood by all the readers. There’s a sweet spot to make it authentic but authentic to the stories.”

The stories of romance, battles, intrigue and time travel meant that Outlander was a shoo-in for the screen. It was clear that the books had outgrown the scale of a single film and television was a better medium, with Gabaldon on hand as consultant. This has been another way of getting to know the historic buildings that “play” the novels’ fictional castles and locations.

“To begin, I wrote one episode, which we filmed at Drumlanrig Castle. That was an eye-opener. There was a long, drawn-out discussion about which door should be used for an entrance until the director said, pretty firmly, ‘I don’t care, just get me a fire in that fireplace!’.

The National: The Outlander television adaptation filmed at Drumlanrig Castle in ScotlandThe Outlander television adaptation filmed at Drumlanrig Castle in Scotland

“Suddenly two people appeared with measuring tapes and torches to examine the chimney to make sure they could place the portable gas fires they use – it’s easier to control the flame to exactly the level required. I was amazed to see how every detail was looked after.”

Gabaldon’s knowledge of every aspect of the story has been crucial to getting the crew out of the holes that the restrictions of filming in historic locations can bring. When Claire was held captive in a castle, she tried to open a massive mahogany door with a hook. First they had to check that the tool she was using was historically accurate, but then there was the small matter that even the 4ft camera couldn’t fit into the space and get the required close-up shot of Claire’s hand opening the door.

“While all this was happening, someone told me that this was the actual room that Bonnie Prince Charlie had stayed in while he was at the castle – and that it had a secret door. So I said: ‘Well, why don’t we have the character Mary come through the secret door and save her?’ Working out that tiny detail took about 45 minutes.”

The rise in numbers to the attractions used in Outlander is clearly a huge economic benefit, but care needs to be taken when heavy modern equipment and large film crews roll into some fragile historic locations. “Yes, there certainly needs to be some careful negotiation with Historic Scotland about what can and what can’t be done.”

The ninth novel in the main Outlander series, Go Tell The Bees That I Am Gone, will appear on shelves at some point this year. Gabaldon has previously said that the main series will end with Book 10 –and she knows how it will end.

“I’ve known that for 15 years,” she says. “When I say that, I know what the final scene is, but I don’t know exactly what the tenth book will be.”

The fans, who Gabaldon communicates with fairly regularly over social media, need not cry into their Jamie pillows. The end of the main book series might be in sight, but the universe is ever expanding.

“While the main story will come to a satisfactory conclusion, I don’t have to leave these characters behind. I’ve been writing the associated novellas and the novels concentrating on the Lord John character – there will be at least one more novel there. There will be one or maybe three books about Master Raymond. Also, while I’m writing book 10, there will be a prequel written about Jamie Fraser’s parents.”

Gabaldon is still fascinated with that period. “Scotland is certainly going through a different kind of turbulence at the moment, but I think the great novels about that are a way off.”

The National: Outlander's Jamie and Claire have a devoted fanbaseOutlander's Jamie and Claire have a devoted fanbase

Like JK Rowling, people are always trying to get a handle on her secret. How do you create something that almost takes on a life of its own?

“Rick Rankin [Outlander’s Roger Wakefield] and I went to lunch and he told me he wanted to write, but didn’t have the time. I told him that no-one does, but if you write for 10 minutes every day, by the end of the year you’ll have a short novel. If you don’t, you won’t. If you want to write you have to write.”

When Outlander was being storyboarded for the small screen, Gabaldon says she was determined that Scotland should be as much of a character as Claire or Jamie or Murtagh.

When asked what she meant by that, how she would describe Scotland if it was a person, she pauses for a good while. “Well… someone asked me if I could see Scotland reflected in my books, and I said I could see its dramatic personality.

“At its root, I see Scotland as extremely honest, there’s nothing sneaky about it. The Scots can also certainly stand their ground.

“However, there are high mountains, which are honour and glory and nobility, and then we descend into the glacial valleys where there are deep, dark, impenetrable lochs. Scotland is a complete story in itself.”

Aside from a few authorly linguistic flourishes, Gabaldon is also straight to the point and unflinchingly realistic. Maybe there’s some Scottish in her after all.

The Ladies of Lallybroch

The Ladies of Lallybroch are a community of Outlander fans who take their name from the fictional Fraser estate in the series. They contributed to the restoration of the Culloden Memorial Cairn, originally erected on the site of the famous battle in 1881. The battle featured in the first two of Gabandon’s Outlander books. The site has become hugely popular with Outlander fans visiting Scotland.