On Thursday, London mayor Boris Johnson lobbed a very public insult at former Massachusetts governor Mitt Romney.

“There are some people who are coming from around the world who don’t yet know about all the preparations we’ve done to get London ready in the last seven years,” Johnson told a crowd, gathered for the Olympic cauldron-lighting ceremony. “I hear there’s a guy called Mitt Romney who wants to know whether we’re ready. He wants to know whether we’re ready.”

During an Olympics eve rally in Hyde Park on Thursday, London Mayor Boris Johnson slammed Mitt Romney's remark that he foundsecurity at the games "disconcerting," asking the crowd to an eruption of applause, "Are we ready? Yes we are!"

But that’s nothing compared to what Johnson once wrote about George. W. Bush: “The President is a cross-eyed Texan warmonger, unelected, inarticulate, who epitomises the arrogance of American foreign policy.”

Or Tony Blair: “He is a mixture of Harry Houdini and a greased piglet. He is barely human in his elusiveness. Nailing Blair is like trying to pin jelly to a wall.”

So who is Boris Johnson? Someone far more likely than Romney to say the wrong thing.

A member of the Conservative party, the floppy-haired Johnson started out as a newspaper reporter. He was fired from the the Times of London in the 1980s for making up a quote, an incident he later called his “biggest cock-up.” It didn’t end his media career; from there he went on to work for the Daily Telegraph and then The Spectator, a conservative magazine.

Johnson continued to write for the Spectator after becoming a Conservative member of parliament from Henley. (One campaign slogan: “Voting Tory will cause your wife to have bigger breasts and increase your chances of owning a BMW M3.”)

It was at the Spectator that Johnson wrote in a 2004 editorial declaring that Liverpool was wallowing in “disproportionate” grief over the beheading of a local in Iraq. The Tory party leader ordered Johnson to the city on an apology tour.

A few weeks later he was fired from his post as culture minister anyway, over an affair with a columnist that he had denied as “an inverted pyramid of piffle.”

In 2005 he stepped down as Spectator editor at party leader David Cameron’s request, to become shadow minister of higher education. In 2007 some called for him to be sacked from that post after Johnson called Portsmouth “one of the most depressed towns in Southern England, a place that is arguably too full of drugs, obesity, underachievement and Labour MPs.”

Conservatives settled for Johnson in the 2008 mayoral race after a long list of candidates turned the party down, according to a recent biography.

Johnson’s 2008 mayoral victory was a surprise, largely seen as rebuke of the Labor government then in power. He’s been criticized for delegating too much, but Johnson was reelected this past May, even as Conservatives lost nationally. He still writes columns, now for the Daily Telegraph, on “the injustices and absurdities of life, from bicycle thieves to petty bureaucracy.”

While he considers himself a conservative through and through, his views on Islam have moderated considerably and he supports gay marriage, expanded bicycle networks and a higher minimum wage. The mayor also has a cultured side; at an Olympic gala last week, he recited a poem in ancient Greek.

All in all, its a history of comments far more incendiary — and interesting — than Romney’s Olympics evaluation.