Why Stanley Spencer tore apart his family for a lesbian muse

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She also has a vivid memory of watching her father paint his masterpiece, the 19 pictures in the First World War memorial chapel at Burghclere in Hampshire, created between 1926 and 1932.

“When I was little I was taken to watch Daddy work on the chapel,” she says. “I loved his pictures. Even if I didn’t understand what they were all about, I could understand the humanity behind them.”

Spencer was driven by an obsessive sexuality and an intense Christian mysticism that he rooted in his hometown of Cookham in Berkshire. It would help him to produce some of the most distinctive English paintings of the 20th century, including the famed altarpiece at Burghclere where, in a jumble of white crosses, soldiers clamber out of their own graves, resurrected to eternal life.

“It seemed to me that my daddy was a magician,” says Shirin. But the magician was about to meet an enchantress, and the strange affair that followed would take Shirin’s childhood and destroy her mother’s life.

Spencer was born in Cookham in 1891 and went to the Slade art school in London before meeting Hampstead artist Hilda Carline in 1919. She quickly became central to his work, posing for the figure of Christ in The Betrayal (1922/23), where Jesus is captured in a backyard in Cookham rather than the Garden of Gethsemane.

They married in February 1925 and Shirin was born the same year. A sister, Unity, was born in 1930 and in 1932 Spencer took his family back to Cookham. The house next door was occupied by two artists in their early 40s, Patricia Preece and Dorothy Hepworth.

Preece passed off Hepworth’s more accomplished work as her own and lived off the income provided for Hepworth by her father. Moreover, the two women were in a physical relationship.

But Spencer, naive or simply ignorant of her sexuality, was smitten and began to paint Preece obsessively. Depressed, Carline retreated to Hampstead. “There wasn’t room for me at Hampstead,” says Shirin. “So I was given to a relative who lived nearby.”

The relative, Mrs Harter, renamed Minnehaha by six-year-old Shirin, moved to Epsom, Surrey, so she was further separated from her mother and sister and cut off from Stanley, who rarely came to Epsom.

Shirin took it hard. “I felt like I’d been exiled. And Minnehaha did something that I found difficult to get over. I was ill in bed with a temperature and it happened that Patricia was visiting friends in Epsom, so she came to visit the house. Minnehaha brought her upstairs to see me. I was in bed; I couldn’t escape her. When she came in the room, I just gasped. I knew what she was doing to Daddy.”

Preece had already destroyed one public figure, WS Gilbert of Gilbert and Sullivan fame, who died trying to save her from drowning in 1911. Spencer was convinced that he was destined to be with Preece and pressurised Carline into a divorce in 1937.

Preece and Hepworth (whose father’s business had failed) were now free to take Spencer for all he was worth. After the marriage, also in 1937, Spencer wasn’t even allowed to share a wedding bed with Preece and immediately after the service, she and Hepworth set off without him for the honeymoon in the West Country. Stanley stayed in Cookham to finish a picture.

“Before the wedding, Patricia wrote to Mummy saying come down and collect anything that belongs to you, then come on with Stanley if you like. Come on the honeymoon!” scoffs Shirin. “But he knew what would happen when they were alone together.”

Carline duly arrived from London and spent the night in Spencer’s bed. Preece would use this as an excuse never to let Stanley touch her. After the marriage, Stanley asked Carline to join him and Preece in a ménage à trois. She refused, but did sit for a remarkable painting, Hilda, Unity and Dolls (1937).

Unlike the folkish whimsy of some of the Cookham paintings this is a searingly honest picture. Carline is so pained by events, she’s turned her face away. Unity fixes her eyes on the father who is abandoning her. Shirin, of course, is absent.

The full and bitter irony of Stanley Spencer’s foolishness is revealed in another painting from the same year. In Double Nude Portrait: The Artist and his Second Wife (1937), a naked Preece looks away, uninterested, as an equally naked Spencer crouches over her. It is a bleak and unsettling work, known as the leg of mutton nude because of the joint of meat in the foreground and like Hilda, Unity and Dolls another sign, perhaps, that Spencer deliberately generated misery to improve his art.

It is also a picture Shirin has never been able to look at. “I couldn’t cope with it at all,” she says. “I found the picture so painful, because nothing happened between them [sexually]. She couldn’t respond properly and I think he painted it because, though he couldn’t really have her in a complete way, he could have her as a picture. I hate looking at it.”

Spencer’s relationship with Preece and its consequences for their children were too much for Carline to bear. “You deserve to be cursed,” she wrote to him from Hampstead.

Perhaps he was cursed. Shortly after the marriage, Spencer signed over the deeds of the Cookham house to Preece. She forced Spencer to leave, rented out the property and lived on the proceeds. Within two years Spencer was penniless and living in a bedsit in Swiss Cottage in London.

He simply kept painting, sealing the room and embarking on the Christ in the Wilderness series of paintings, in which a wandering Jesus celebrates the entirety of God’s creation. In the first painting Christ looks down with infinite love at the scorpion he holds in his hand.

“I’m a Scorpio,” Shirin says. “So I like to think that picture is my dad saying, ‘You’re all right, girl.’”

Hilda Carline died of breast cancer in London in 1950. “Daddy was at the hospital every day,” says Shirin, though, true to form, he missed her final moments. “He wasn’t actually in the room with her when she died. He’d gone downstairs, to get a cup of tea.”

Spencer would have other lovers, though Preece would never be one of them. His reputation grew throughout the 50s and he was knighted in 1959. He died the same year from cancer, aged 68, at the Canadian War Memorial Hospital in Cliveden.

Unity, a talented artist herself, struggled with depression throughout her life and the relationship between the two sisters, one who’d been abandoned, the other who’d borne the brunt of her mother’s depression, would often be troubled.

The two were brought back together by Unity’s son, John Spencer. The last of Stanley Spencer’s line, he presides over the artist’s estate and the ongoing publishing of his remarkable catalogue of correspondence, much of it to Hilda Carline.

Thanks to John, her daughters lived together again for just over a year until Unity’s death in October last year.

Patricia Preece died in 1966. Until the end she insisted on being addressed as Lady Spencer and collected the pension that was her due as the widow of a knight.

Shirin, although a committed Christian, struggled to forgive her. “When I was young I just thought this is how things were. But as I got older, and realised what Patricia had done, she became the one person I really hated. She was never going to be a wife.

“Our mother cared so much about Daddy. When she realised that Patricia wasn’t interested in sex with a man, she said, ‘Perhaps she could have something done about it.’ She thought that something could be done to help Patricia, so that Patricia could be a proper wife to him.”

Fifty-nine years after his death, Spencer’s cruelty to his wife and children remains hard to understand. He left behind a body of work that is intoxicated by the hope of resurrection and personal redemption, and yet he cast his daughters into a pit of misery and left them there.

It begs the old question: does good art justify bad behaviour? “You must understand,” says Shirin. “Genius is like another child. More than that, your most precious child. And it’s the child you’ve got to look after.”

Arena: Stanley and His Daughters is on Sunday 10.00pm BBC4