Australian director Justin Kurzel said shooting Macbeth in the Scottish Highlands in winter was both "horrendous" and inspiring.
Kurzel's adaptation of one of Shakespeare's best-known plays, starring Michael Fassbender and Marion Cotillard, was shot over 36 days in some of the country's most remote and exposed locations.
The environment posed challenges for the cast and crew but the director told a preview audience in Edinburgh that filming in Scotland "was everything to me".
He said: "I found it so exciting, the idea of doing Macbeth in its homeland, and the idea of embracing that landscape.
"I remember my first trip to Skye - it was unbelievably beautiful but also frightening how majestic, how kind of ancient it was. You could kind of imagine perhaps witches and spirits.
"We travelled everywhere and we landed around Skye and Applecross and they were the areas that kind of encapsulated the kind of spirit that we felt we wanted to surround Macbeth with."
Macbeth is the tragedy of a Scottish warrior, played by Fassbender, who is haunted by his own ambition, his greed for power and a prophecy that he will one day become King of Scotland.
Cotillard plays Lady Macbeth who is grieving the loss of their child and spurs her husband to kill King Duncan so they can assume the throne.
Also shot on location at Bamburgh Castle in Northumberland and Ely Cathedral in Cambridgeshire, the film was screened at the Cannes Film Festival last month and is set for release in UK cinemas on October 2.
David Thewlis stars as King Duncan, Paddy Considine as Banquo and Sean Harris as Macduff.
Kurzel, who previously directed the Adelaide-set Snowtown (2011), said shooting Macbeth on location was at times " unbelievably horrendous".
He told an audience at the Cameo cinema: "It's unforgiving, that land, in the winter.
"I did the location scouts in the summer and it seemed so charming, so awe-inspiring, but do-able.
"Then we arrived and you are watching your production designer fly across the camera, picked up by the wind, and Marion Cotillard kind of disappearing into a bog.
"It's really formidable, but it was also what we were getting most inspired by, this kind of unforgivable land that we were trespassers on, in a way. I wanted the film to look 'hard'.
"I wouldn't have done the film if I couldn't shoot here."
He added: "I started seeing it as a Western - there was something interesting about these characters being isolated and brutalised by their environment."