LONDON (AFP) - Instantly recognisable with his mop of blonde hair, Mr Boris Johnson's bumbling but breezy attitude earned him a string of improbable political victories, including Brexit, but has enraged and offended in equal measure.
The Conservative MP is favourite to replace Mrs Theresa May as party leader and prime minister, having proved his pedigree as a winner by being elected twice as mayor of London, a cosmopolitan and normally left-leaning city.
Mr Johnson's decision to back the campaign to leave the European Union in 2016 was also viewed as a game changer in the push for Brexit.
It lost him many friends and he drew criticism for making misleading claims during the campaign.
However, it made him a strong favourite for prime minister when the post opened up in the chaos after the referendum - only to lose out when his main backer turned against him.
His subsequent appointment as foreign minister was a surprise, given his inclination for acting the clown - blundering into a series of diplomatic rows with his seemingly off-the-cuff remarks.
But when he quit after two years in protest at plans to retain close ties with the EU after Brexit, many Conservative activists hailed his decision and he once again moved centre stage.
One of a rare-breed of politicians known simply by his first name, "Boris" was born in New York in 1964 as Alexander Boris de Pfeffel Johnson into a competitive, high-achieving family.
His sister Rachel, a journalist and writer who later went on to stand as a candidate for anti-Brexit party Change UK, told her brother's biographer that as a child he wanted to be "king of the world" when he grew up.
Mr Johnson won a scholarship at the elite Eton school and read classics at Oxford University, where he was a member of the Bullingdon Club, an all-male dining society known for rowdy behaviour.
He became a journalist and was initially sacked from The Times for fabricating quotes. He then worked for The Daily Telegraph, as editor of Spectator magazine and wrote several history books.
He made a name for himself as the Telegraph's Brussels correspondent mocking the EU's institutions and rules.
He was among the first to peddle "Euro-myths" about bans on bendy bananas and square strawberries, a style of reporting about the bloc that became a staple of the British press.
Mr Johnson became MP for the then opposition Conservatives in 2001 and was later appointed as the party's arts spokesman, before being sacked over accusations of lying about an alleged extra-marital affair.
However, the persona he cultivated as the plucky British amateur fighting a political machine increasingly dominated by spin remained popular with the public, winning him the London mayoral elections in 2008 and 2012.
His role overseeing the 2012 Olympic Games - and memorably getting stuck on a zip-wire while celebrating Team GB's first gold medal - gained him a global profile.
Critics say he left no lasting legacy beyond some new cycling infrastructure, but Mr Johnson's brand of liberal conservatism proved appealing to urban voters in a way few of his party colleagues could match.
The year before he quit as mayor, Mr Johnson returned to the House of Commons as MP for an area west of London.
Among his promises was to oppose the expansion of London's Heathrow airport, although he was not present for a key vote on the project after hastily arranging a trip to Afghanistan in his role as foreign minister last year.
'LEAST SUCCESSFUL' DIPLOMAT
His appointment as Britain's top diplomat in 2016 was viewed as a canny move by new prime minister Mrs May to keep him from building up a domestic power base, but risked being deeply awkward.
He once wrote about Africans as "flag-waving piccaninnies" with "watermelon smiles", and made a racially-charged quip about former US president Barack Obama.
In office he made some major errors, notably in suggesting that a British-Iranian woman held in Tehran on sedition charges may have been training journalists - something her family strongly denies, and fear jeopardised her case.
The Chatham House think tank concluded he was Britain's "least successful" foreign minister since World War II, noting: "Where gravitas and grasp of detail were needed Johnson supplied bon mots."
Nor did he stay out of domestic politics - Mr Johnson repeatedly challenged Mrs May's Brexit strategy through newspaper articles. When he finally quit as foreign secretary, she seemed relieved.
But he stayed in the headlines, sparking a national debate in August 2018 with an article saying that Muslim women who wore the face veil looked like "letter-boxes" or "bank robbers".
His supporters suggested he was merely raising the issue of the compatibility of face veils in liberal societies, but critics suspected it was a cynical move to cement his populist credentials.
Mr Johnson's political shadow grew increasingly large as Mrs May's authority weakened, tidying up his trademark locks, losing weight and going public with his new girlfriend in apparent preparation for an upcoming contest.