Steve Bannon, the Breitbart boss and Trump campaign CEO, runs a website that filters so-called “alt-right”, white nationalist views into the mainstream. He has been accused of racism and anti-Semitism. And now, as the newly appointed chief strategist and senior counselor to the President-elect, his opinions will be whispered into the ear of the leader of the free world.

A former US Navy officer, Harvard business school graduate, Goldman Sachs investment banker and Hollywood producer, Mr Bannon started his fourth or fifth career as a right-wing provocateur by releasing a handful of polemic documentaries. He became executive chairman of Breitbart News in 2012, a job he will quit to take up his new post in the Trump White House.

The ultra-conservative site is known for such liberal-baiting headlines as “Would you rather your child had feminism or cancer?” and “Birth control makes women unattractive and crazy”. It has described the confederate flag as a symbol of a “glorious heritage” and accused President Obama of crying “phony fascist tears” over the children killed in a mass shooting.

In 1996, Mr Bannon was charged with misdemeanor domestic violence and battery after an incident involving his ex-wife. The case was dismissed when prosecutors were unable to contact her. A decade later, in a 2007 court filing, the same ex-wife accused him of making anti-Semitic comments about a private school to which the couple planned to send their daughters.

Donald Trump's most controversial quotes Show all 14 1 /14 Donald Trump's most controversial quotes Donald Trump's most controversial quotes On Isis: "Some of the candidates, they went in and didn’t know the air conditioner didn’t work and sweated like dogs, and they didn’t know the room was too big because they didn’t have anybody there. How are they going to beat ISIS?" Getty Donald Trump's most controversial quotes On immigration: "I will build a great wall — and nobody builds walls better than me, believe me —and I’ll build them very inexpensively. I will build a great, great wall on our southern border, and I will make Mexico pay for that wall. Mark my words." Reuters Donald Trump's most controversial quotes On Free Trade: "Free trade is terrible. Free trade can be wonderful if you have smart people. But we have stupid people." PAUL J. RICHARDS | AFP | Getty Images Donald Trump's most controversial quotes On Mexicans: "When Mexico sends its people, they’re not sending their best. They’re sending people that have lots of problems. They’re bringing drugs. They’re bringing crime. They’re rapists." Getty Donald Trump's most controversial quotes On China: "I just sold an apartment for $15 million to somebody from China. Am I supposed to dislike them?... I love China. The biggest bank in the world is from China. You know where their United States headquarters is located? In this building, in Trump Tower." Getty Images Donald Trump's most controversial quotes On work: "If you're interested in 'balancing' work and pleasure, stop trying to balance them. Instead make your work more pleasurable." AP Donald Trump's most controversial quotes On success: "What separates the winners from the losers is how a person reacts to each new twist of fate." Donald Trump's most controversial quotes On life: "Everything in life is luck." AFP Donald Trump's most controversial quotes On ambition: "You have to think anyway, so why not think big?" Getty Images Donald Trump's most controversial quotes On his opponents: "Bush is totally in favour of Common Core. I don't see how he can possibly get the nomination. He's weak on immigration. He's in favour of Common Core. How the hell can you vote for this guy? You just can't do it." Reuters Donald Trump's most controversial quotes On Obamacare: "You have to be hit by a tractor, literally, a tractor, to use it, because the deductibles are so high. It's virtually useless. And remember the $5 billion web site?... I have so many web sites, I have them all over the place. I hire people, they do a web site. It costs me $3." Getty Images Donald Trump's most controversial quotes On Barack Obama: "Obama is going to be out playing golf. He might be on one of my courses. I would invite him. I have the best courses in the world. I have one right next to the White House." PA Donald Trump's most controversial quotes On himself: "Love him or hate him, Trump is a man who is certain about what he wants and sets out to get it, no holds barred. Women find his power almost as much of a turn-on as his money." Getty Images Donald Trump's most controversial quotes On America: "The American Dream is dead. But if I get elected president I will bring it back bigger and better and stronger than ever before and we will make America great again." GETTY

As they discussed the Archer School for Girls in Los Angeles, she claimed, Mr Bannon “went on to say the biggest problem he had with Archer is the number of Jews that attend. He said that he doesn’t like Jews and that he doesn’t like the way they raise their kids to be ‘whiny brats’ and that he didn’t want the girls going to school with Jews.”

Mr Bannon pleaded not guilty to the domestic violence charges. The couple ultimately did send their daughters to Archer, and, after the court documents emerged this year, he denied the “whiny brats” conversation had ever taken place. Many, however, have found some of his on-the-record remarks plenty offensive enough.

John Weaver, the chief strategist for Mr Trump's former Republican primary rival, Ohio Governor John Kasich, was among those who expressed dismay and revulsion at Mr Bannon's appointment to a White House role, describing him in a tweet as a "racist" and "anti-Semite".

In 2010, in an interview to promote a film about right-wing female firebrands such as Sarah Palin and Ann Coulter, Mr Bannon said their success undermined “the progressive narrative,” explaining: “That’s one of the unintended consequences of the women’s liberation movement – that, in fact, the women that would lead this country would be feminine, they would be pro-family, they would have husbands, they would love their children. They wouldn't be a bunch of dykes.”

Now 62, Mr Bannon has made a habit of antagonising the Republican establishment as much as he does the liberal left. At a conservative gathering in 2013, he reportedly called for a populist uprising within the GOP. “It’s going to be an insurgent, centre-right populist movement that is virulently anti-establishment, and it’s going to continue to hammer… both the progressive left and the institutional Republican Party,” he said.

He was, it now appears, describing the Trump campaign. It is perhaps no coincidence that Mr Trump has also been accused of anti-Semitism. In the final days of the election, the Trump campaign released an ad that contained several arguably anti-Semitic tropes, including claims of a global conspiracy and images of the Jewish financiers George Soros and Lloyd Blankfein. In a 60 minutes interview aired on Sunday evening, Trump called on his supporters to "stop" harassing minorities, saying "don't do it. That's terrible." But the news of Mr Bannon's appointment, which broke on the same night, will do little to calm fears.

In a recent profile of Mr Bannon for The Atlantic, Conor Freidersdorf compared Mr Bannon to a Jacobin, the most ruthless and radical group involved in the French Revolution. “Trump is not his idea of a good president of the United States,” Mr Freidersdorf wrote. “Trump is his guillotine.”