His death was an untimely tragedy; his life plagued by drink and depression.

Yet, as a new book reveals, in his final years Charles Rennie Mackintosh found peace.

December 10, 1928. London

Charles Rennie Mackintosh died on a Monday. The fag end of the year, you could say. A mordant thought for a man who died of cancer caused by too much smoking and ­drinking. He was cremated the next day. In a letter written 18 years and a World War later, his friend Desmond ­Chapman-Huston said of the ceremony: “The crematorium chapel is dismal and so was the service.” At least ­Chapman-Huston, Mackintosh’s patron and supporter, had the coffin covered in “lovely silver grey velvet and it made a pleasing background for lots of finely coloured flowers – so that the last glimpse Margaret [Mackintosh’s wife] had of him was quite lovely”.

A small mercy. But then, after a year of ill health, painful treatment and the fading solace of work – fading because it was more and more impossible to carry out – perhaps small mercies were all that was left.

For Mackintosh himself, of course, none of that mattered any more. He was dead at 60, having spent his last days in a nursing home in Porchester Square in London, a few doors from Chapman-Huston’s house. His obituary in The Times was “about as long as that given to the obscurest and dottiest of peers”, ­according to John Betjeman – though The Herald, or The Glasgow Herald as it was then, was rather more generous in its assessment of the artist and the space it devoted to him. Still, it would be another five years – by which time Margaret had died too – before he would be tagged “a neglected genius”.

Neglected in Britain at least. After his death, his reputation remained strong in mainland Europe (a point made in The Herald’s obituary). But it was a reputation based on his days as a young meteor, blazing a trail in the world of architecture with his designs for Glasgow School of Art, Hill House, Windyhill and others; too short a list in retrospect.

By the time of his death, though, Glasgow was 14 years distant and his life had taken on a new trajectory. The story of the last years of Charles Rennie Mackintosh – artist, architect and, these days, brand name – could be described as something of a dying fall, a fall that began when he and Margaret left his home city. Maybe even before that.

I am sitting in James Macaulay’s home in the west end of Glasgow. It’s a house full of books and art and beautiful furniture. An aesthete’s house. And the home of a gregarious, ­clubbable man. Macaulay, author and former senior lecturer at the Mackintosh School of Architecture, has written a new book about Charles Rennie Mackintosh. It is the culmination of almost 50 years of research and ­writing. He wrote his first piece about him back in 1961, and his interest started long before that.

“I was brought up on stories of ­Mackintosh,” he says. “My stepmother moved in those circles and when we were children we used to be taken to the Ingram Street tea room by our mother and she would sit us down and we’d get orange squash and a biscuit and she’d say, ‘Now, look at that fireplace. Look at that ornament.’ When I was young, you could literally walk into the art school and nobody stopped you. And I used to do that.

“I was,” he adds, laughing, “an unusual child. I was very interested in architecture.”

In later years – by the time Macaulay had started writing – the family home contained furniture designed by Mackintosh, furniture he had bought himself. His interest has never waned.

Macaulay’s book covers the life and work of Mackintosh, but today we’re talking about the artist’s last years. That dying fall. Because by the time Mackintosh and Margaret left Glasgow, in 1914, he was in his forties and his best work was behind him. Ahead, in the distance, an ending. But first he had some time in the sun.

May 1927. Port-Vendres

That summer, Charles Rennie Mackintosh painted. An exhibition in London was in the offing and he had 50 canvases to produce. He worked outdoors, crafting visions of the French landscape that foregrounded form and structure.

“In the extreme south of France you get these rocky outcrops, you get these hilltop villages, you get these very compact configurations of dwellings and churches,” explains Macaulay. “It is the spatial relationships and the architectural forms that obviously intrigued Mackintosh. There is no human activity or animal life or anything.” You can see the architect’s eye in his little sketches of ships in the harbour, Macaulay argues.

Mackintosh and Margaret had moved to France in 1923, and arrived in Port-Vendres two years later. “In those days a lot of people could afford to go wandering around the continent of Europe because it was a lot cheaper living there than it was in Great ­Britain,” says Macaulay. “Margaret had a certain amount of money on her own and they seemed to be able to get by in France.

“And of course they lived in hotels all the time. There was no question – as there would be nowadays – of, say, renting a villa and looking after yourself because I’m not sure that Margaret ever actually cooked anything. Living in Hillhead in the early 1900s they were really quite well-to-do and everybody had help of some kind or another. My mother, who was brought up in the 1920s, she had no idea about cooking until she got married. My mother had to learn to cook. She was never a very good cook. And I don’t think Margaret ever cooked. So living in France was really the ideal solution because it was cheap.”

That May, Margaret had to go to London, but Mackintosh stayed on and worked. He would write to his wife of 30 years and tell her about his days in front of an easel, in between being pestered by schoolboys keen to view his works in progress and being plagued by insects. It’s an informal account, affectionate, even passionate. He wrote to her saying that he longed for her return so he could forgo writing. “I prefer a more intimate form of intercourse,” he told her in his “Chronacle” (sic) of that summer.

“You do get the sense that this was a couple who were truly devoted to each other,” says Macaulay.

Alongside that, however, were the first signs of the illness that would soon take over Mackintosh’s life. “My tongue is swollen – burnt and blistered,” he wrote at one point. Later, “a big ‘button’ growing on the right-hand side of the point of my nose” appeared, prompting him to consult a local doctor in the autumn of 1927. His advice was that ­Mackintosh should return to London for treatment. Macaulay suggests it was Mackintosh’s preference for pipe-smoking and whisky that was at the root of his illness. “It’s really pretty lethal, even in this day and age. And it was lethal with him.”

Mackintosh had always been a drinker. There are stories that he would work all night in the offices of the Glasgow architectural firm Honeyman and Keppie, filling page after page with drawings, emptying a bottle of whisky as he did so. But that was par for the course in Glasgow at the time, reckons Macaulay. “I think he drank heavily always. There was very much a drinking culture. People go on about it now, but it’s nothing new. There were all these drinking dens of various levels of respectability all over the city.

“Alcoholism and drunkenness were major problems. They were a major problem in the First World War. That’s why in certain areas the pubs were nationalised – to curb the drinking of the workers in the munitions factories.

“I remember an old lady said to me they all drank, even the women. And Mackintosh and his group seem to have been a part of a rather bohemian set. And they weren’t popular with other artists and architects and this comes out quite clearly in the few reminiscences that we have – that they were slightly apart and they were looked on with disapproval.”

Macaulay even suggests you can see the intertwining of work and drink in ­Mackintosh’s drawings. He cites the architect’s drawing of Maybole Castle. “If you actually go to Maybole, you think, ‘Where did he position himself to make this drawing?’ Clearly it was the pub. It was the pub directly across the road. And there are quite a lot of pieces of written evidence that when he went on sketching tours he behaved very badly and was thrown out of places, so he seems to have drunk all through his life. It seems to have been quite a big problem.”

Was he an alcoholic? “I don’t know,” says Macaulay. “Nobody actually said he was an alcoholic, but there were quite a lot of references by other people to his ‘problem’. There was a house out near Killearn which came to ­Honeyman and Keppie, and Mackintosh was working on it. Now, the story I heard was that he was taken off that job and it eventually went to somebody else in the firm, and the reason he was taken off that job was that he went out to Killearn and he got as far as The Black Bull and that’s as far as he got.

“Maybe by that time he was bored of the kind of ­architecture he was doing, because any job becomes routine. He may have been bored by the client, I don’t know. I think the client wanted things Mackintosh probably didn’t want to deliver. He certainly had a drink problem, there’s no doubt. People have tried to deny it, but sadly I don’t think one can deny it.”

Of course, Mackintosh’s bohemianism is in some ways a mark of his artistic individuality. And it was a reference point for many of his clients, Macaulay believes. “It is interesting that his clients were slightly flamboyant and certainly not the run of the mill. Although Walter Blackie at Hill House was in many respects a very conventional figure, he was a very, very successful publisher and a man who was used to dealing with slightly larger-than-life characters, because many authors are. He was already the patron of authors and artists and illustrators, so in a way he could take on board Mackintosh. And they ­obviously got on extremely well together.

“Kate Cranston (who commissioned Mackintosh to design the interiors of her famous Glasgow tea rooms) was certainly a very ­flamboyant self-publicist. Even the way she dressed, in this slightly old-fashioned way. She was a very small lady, but she always wore a very large crinoline. And she used to drive into town in her carriage laden with flowers for the restaurants. She was a very, very well-kent figure, and highly individualistic.” Francis Newbery at Glasgow School of Art came from the same mould and gave Mackintosh free rein to design a school that was both a working building and a work of art.

By contrast, John Keppie’s patrons were, says Macaulay, “the kind of folk who join a golf club or were members of the trades house, and they’re not usually the most adventurous in terms of art and patronage”. The tension between the two men was inevitable – John Honeyman had already retired – and it can hardly have been a surprise when Mackintosh, having suffered a bout of pneumonia, opted to leave the architectural practice in 1914. “He had been ill, obviously, one knows that. But I think in many respects he was probably burnt out,” Macaulay says. “I’ve seen this with people in other fields round about the age of 45. They’re burnt out, they’re finished, they’re shells. And I think by that period Mackintosh was burnt out.

“There were all the strains and stresses – financial strains, professional strains – but he was obviously an obsessive because he could design anything and everything. But he would focus very intently and deeply on a project and give it everything and it didn’t matter if it was designing a knife or the facade of a ­building. He was a very natural designer, a very gifted designer, a very original designer, but the intensity of that, I think, took its toll.

“Lots of people suffer from depression, but if you’re creative the mood swings are greater, the liability to suffer depression is greater, because you’re never satisfied with what you’re doing. And you know you can’t be perfect, so you do suffer from depression, and Mackintosh obviously suffered from depression.”

Summer 1928. London

On his return to London, Mackintosh was admitted to Westminster Hospital, where he was diagnosed with cancer of the tongue. Margaret arranged to stay with Chapman-Huston and brought her husband food while he underwent radium treatment. “It was absolutely ghastly,” says Macaulay. “There weren’t any of the palliatives that we have today. It was just gruesome.”

The hospital discharged him “temporarily”, Chapman-Huston wrote in his 1944 letter. “I don’t know what Margaret thought, but he considered it a good sign. I did not. I feared they considered his case incurable – but did not care to say so.”

At the start of the 1920s the Mackintoshes had lived in Chelsea, close to the Scottish artist JD Fergusson and his partner Margaret Morris, a dancer. Mackintosh had hoped to revive his architectural career, but money was tight and plans constantly scaled down. The only project that was finished was a studio block for the artist Harold Squire. Perhaps it was little wonder that the Mackintoshes left for France. Now, having been forced to return, they moved into a small furnished house in Hampstead. He wanted a garden to sit in, shaded by the cover of a tree, and “he sat out a great deal that summer”, Chapman-Huston recorded. His last taste of sunlight.

The house was in a street called Willow Road. Today it’s a rather anonymous street but you could find in the name an aptness if you so desired. “You get the Willow ­Restaurant and the Willow Tea Room and trees are a very important part of his life,” Macaulay points out. “You get all this symbolism of trees on buildings, in the buildings and so on, and he ends up sitting under a tree in Willow Road in Hampstead. And somehow you feel it has come full circle.”

The summer faded and so did Mackintosh. He and Margaret had to move out of Willow Road after a falling-out with the landlady. They became Chapman-Huston’s guests in Porchester Square but after a while the stairs became too much for Mackintosh and he moved up the road into the nursing home while Margaret stayed on.

Chapman-Huston bought a couple of the watercolours Mackintosh had completed the previous summer for the London exhibition. He took them into the nursing home for Mackintosh to sign them: the last time he held a pencil, according to his patron.

2010. Glasgow

This December, Charles Rennie Mackintosh will have been dead for 82 years. After his death, Chapman-Huston brought Margaret her husband’s ashes. She wanted to scatter them in Port-Vendres – “where he was,” Chapman-Huston notes, “so happy”. Far from the city of his birth.

Then again, it’s in the city of his birth that his memory lives on, is still strongest. His marks are all around the city – in stone and glass and delicate, pure ornament. People come from all over the world to see those marks. To stand in front of Glasgow School of Art and take it in.

“Why do the paintings and the architecture appeal to people?” James Macaulay asks. “I think they appeal to people because we can relate to them and we do feel that they are not Victorian. Mackintosh, after all, is a Victorian – and that’s not something that people comprehend. They don’t see him as a Victorian. They see him as somebody of their own time. He doesn’t seem a remote figure. Also, he seems very human because of the tragedy of his life, because of his personal behaviour, his financial circumstances. One does feel that here is a human being. He’s borrowing money, he’s trying to make a living, he’s ill, he’s really going from pillar to post and we can all sympathise with him because we’ve all been there.”

In the end, cold stone is all that marks our passing. For most of us it’s the cold stone above the grave, but Mackintosh left a greater ­memorial than most. In the end, though, Macaulay’s epitaph is perhaps just as good. “Here is a human being.” For all his great gifts, that’s all Charles Rennie Mackintosh was. Human. It’s all any of us are. It’s enough. It’s everything.

Charles Rennie Mackintosh by James Macaulay is published next month by WW Norton, priced £42. James Macaulay will be speaking at Blackwell Bookshop, South Bridge, Edinburgh on Thursday, July 8, at 6.30pm. The event is free but ticketed: for tickets call Blackwell on 0131 622 8222.