The Prime Minister's mother has died aged 79, 'suddenly and peacefully,' at a London hospital.
Artist Charlotte Johnson Wahl was diagnosed with Parkinson's Disease aged 40, and has lived in a small Notting Hill flat with her carer for several years.
The Prime Minister's relationship with his late mother remains something of a mystery, though he commissioned her to paint an image of London for his office when he was mayor, and in a brief gaffe, suggested he hoped to see her on Mothers' Day, despite Britain being in lockdown.
But during his reportedly chaotic and difficult childhood, Boris, the eldest of her four children, was close to his mother and protective of her. She encouraged him in his interests and fostered his precocious cleverness, but also later admitted that he had witnessed her being hit by his father, Stanley Johnson, on multiple occasions.
After a happy childhood growing up in St John's Wood as one of five, with strongly liberal parents who campaigned for human rights, Johnson Wahl went to Cheltenham Ladies' College.
She then went on to Oxford, where she met Boris's father, Stanley Johnson, and they married at Marylebone Register Office before her course was completed, as she took a year out to follow him to America.
According to Boris Johnson's biographer, Tom Bower, Stanley Johnson's 'bluster and bonhomie camouflaged the scars of his own childhood.'
Reportedly, Johnson Wahl recalled him hitting her 'for caring too much about her friends', a pattern of abuse which allegedly continued throughout the Prime Minister's childhood, until the divorce in 1979.
Already an anxious child, Wahl Johnson recalled toddler Boris's reaction to meeting his baby sister Rachel: 'His look was shock, disbelief and fear.'
Watch: Boris Johnson meets children
Clever and quiet, aged just three, he told his mother that he 'wanted to be World King' after reading a picture book on ancient Greece.
Despite her well-off aristocratic upbringing, Johnson Wahl was left to struggle as a single parent when Stanley Johnson headed off to explore the rainforest as a passionate environmentalist.
The family moved to a farmhouse which was dilapidated, mouldy and untidy, and Charlotte and the children were regularly ill as a result, with Boris - then known as Alexander - enduring periods of deafness due to grommets.
Johnson Wahl suffered a breakdown in 1974, when Boris was 11, and was in hospital for eight months, leaving Boris, Rachel, Jo and Leon with their father.
She was eventually admitted to the Maudsley Hospital in London, suffering from severe depression coupled with "anxiety and compulsive rituals so severe that her hands bled from constant washing."
Wahl Johnson was subject to electric shock therapy and aversion therapy, before being transferred to another hospital.
Read more: Boris Johnson’s mother dies aged 79
"Looking back, she recalled, the marriage was ghastly; terrible."
Boris knew about the abuse, and had witnessed it, she added. Rachel Johnson later described the marriage as 'ice storm-esque', a reference to the film about a warring '70s couple.
"Her stoic bravery taught Boris never to reveal vindictiveness or bear grudges", Bower writes in The Gambler, his biography of the Prime Minister. "He learned to act without revealing his motives."
Despite everything, in a rare admission of vulnerability, the PM said in 2004, "I was upset when they broke up."
His mother moved to a small flat in Notting Hill, earning a living painting portraits or friends and contacts such as Jilly Cooper and Joanna Lumley, though Rachel later recalled "we had to bring ourselves up... there wasn't much to eat."
Johnson Wahl refused to accept any money from Stanley Johnson post-divorce, and later commented,
"Once I sent the boys to the market to buy a turkey for Christmas and they came back with a capon because turkey was too expensive. So Christmas dinner was rather small that year. It was like something out of Dickens.”
She later remarried and moved to America, but returned to London after she was widowed in 1996.
In his adult life, Johnson Wahl rarely commented on her children's public lives, but told a journalist in 2015 that Boris was “soft-hearted” and in 2008 said she felt “protective of him”.
Looking back on their childhoods, she added, "They were quite a handful but I loved them tremendously. I taught them very odd things that I wanted to know, like how to draw a squirrel. It was such fun, so cosy."