In late October 1968, Richard Burton wrote an entry in his diary, a habit he maintained for almost his entire adult life. It read: ‘I spent most of yesterday in a bath with a lot of body make-up on, which meant when I came home, that Elizabeth had to wash my back. I was back to the mines again, and the wives washing their husbands’ backs clean of the grime of the colliery.’

It’s an incredible comparison to make. Here is the most celebrated actor in the English-speaking world, being scrubbed down by the most beautiful woman in the world, and yet Burton’s mind is not on the curvaceous form of his wife, Elizabeth Taylor, nor on their yachts, mansions and diamonds. His mind is, once again, fixated on his childhood and the coal seams of South Wales that earned his family a dangerous yet proud living.

As Mr Burton, a new film focusing on Richard Burton’s childhood, comes to our screens, there is now an entire generation with no first-hand experience of watching Burton on stage or seeing a new film of his on the big screen. Dying at the age of just 58 in 1984, Burton’s legacy as one of the 20th century’s greatest actors only touches at the fringes of the story of a man whose fame, at its zenith, could only be rivalled by royalty and The Beatles.

Burton was a totemic star whose demons, primarily alcohol, would see his career arc into a long decline during the 1970s and 1980s. Remaining remarkably lucid and self-deprecating, despite the oceans of alcohol he immersed himself in, one of Burton’s favourite topics to discuss in his later years was that of coal mining.

‘I was informed from birth that the toughest thing on earth was a Welsh miner,’ wrote Burton in his diary in September 1971. ‘I believed it and it got me into more fights than one would have thought possible. I’m still likely to have a go, though I know that at my age and condition, I stand not a chance.’

Burton was the twelfth of 13 children born to a mother who died when he was two. Growing up in the village of Pontrhydfen, South Wales, he was described in one obituary as ‘a plump, roughshod primitive who spoke no English up to the age of 10.’

Educated by a schoolmaster named Philip Burton (who would become his guardian), the young Richard Jenkins would go on to take his tutor’s name. Teaching the boy to speak English, hold a knife and fork and to study the classics, it became clear from an early age that Burton’s formidable presence, looks, confidence and ability to learn would render him unlikely to follow his father and siblings down the pit shaft. And so the idea of stage and screen was born.

Why this prodigious talent would then end up leaving school at the age of just 14 is something that Burton himself was opaque about; merely claiming that ‘something of a small family crisis demanded that I should leave school and go to work.’

His brother-in-law, Elfed, pulled enough strings to get Burton a job in the men’s outfitters department of the local Co-operative store. It was 1941, and with the country at war, it seemed that earlier notions of Burton pursuing a career on stage were about to vanish; pushed roughly aside as a fanciful, impossible dream.

Working at the Co-op was an easy job, a steady job and a job for life. Yet the nascent haberdasher, already an experienced smoker, drinker and chaser of girls, absolutely despised it. Chiefly, as Melvyn Bragg contended in his magisterial biography, Rich, his opprobrium stemmed from a sense of acute embarrassment.

‘He felt humiliated,’ wrote Bragg. ‘Apart from everything else, the soppiness of being a shop assistant in a family of miners brought out a terrible blush for his masculinity, absurd, you might think, but not so absurd if that was your world.’

Hearing tales of his brothers hacking coal from the seam while he measured up shirts and trousers had a profound impact on Burton, which he compensated for at the height of his fame by venerating miners to an extent that went beyond hero worship and into something approaching deism.

“Every boy’s ambition in my valley was to become a miner,” he told the American chat show host Dick Cavett in 1980. “Miners believed themselves to be the aristocrats of the working class… Because there was the arrogant strut of the lords of the coal face. They had these muscular buttocks and the bow legs, and they walked with a kind of arrogance. Everybody wanted to be a miner. They wanted to stand on street corners and look at the posh people pass with hostile eyes.”

As idealised as his vision of the mine shafts he never descended may have been, Burton was pragmatic enough to attempt to lure his siblings out of this perilous livelihood. Yet his eldest brother, David, who first became a miner at the age of 13, refused Burton’s numerous offers to pay him enough so that he need not descend to the bowels of the earth each day.

‘He loved the mine so much that I couldn’t bribe him out,’ Burton revealed not long after his brother’s death. ‘There was no way I could get him out… and you can imagine the constitution of the family, that with his lungs full of dust, he lived until he was 79.’

“Every boy’s ambition in my valley was to become a miner”

Burton’s traduced status as a haberdasher didn’t last long. He quickly gained minor fame (and infamy) in the area for his misuse of wartime clothing coupons at the Co-op. Family members and friends were delighted to find that their coupons would be discreetly returned to them after they’d used them to purchase garments, or they were simply never asked for them in the first place.

This early-years criminal behaviour coincided with Burton joining a local youth club where he played a count in a one-act play based on Les Miserable. His performance was such that the chairman of the Glamorgan Education Committee arranged for Burton to be re-admitted to grammar school. Within a year of his return to the classroom, he turned 16 and embarked on a career that would see him swap South Wales for the stages of the West End with barely a pause for breath.

Yet would Burton have been happier all along as a coal miner? His later, romanticised, view of the industry suggests the development of a carapace that protected Burton from the realities of one of the most dangerous jobs on earth. Yet, perhaps his veneration of mining had a small role to play in his obsession with diamonds - a vice famously shared with Elizabeth Taylor.

It was in 1969, just a year after his vision of the pit baths while being scrubbed by Taylor, that he outbid Aristotle Onassis for the 68-carat stone that would become known as the Burton-Taylor Diamond. Paying $1,050,000, around £16.5 million today, it offered partial proof, not only of Burton’s prodigious wealth, but also of a continuing desire to dig deep, with his wallet rather than a shovel, for the glories that lay deep under the earth’s fragile surface.

Mr. Burton is released in cinemas on 4 April 2025.

Read more: Lara Pulver on MobLand and the importance of humility