Even though defenders, such as House Majority Leader Kevin McCarthy, R-Calif., argue that Bannon shouldn't be held accountable for everything published on the site, critics say that putting Bannon in such a prominent position sets a dangerous precedent.
Here is a list of some of Steve Bannon’s statements and Breitbart articles that have raised eyebrows:
“A Bunch of Dykes”
“The women that would lead this country would be pro-family, they would have husbands, they would love their children,” said Bannon. “They wouldn’t be a bunch of dykes that came from the Seven Sisters schools up in New England.”
Bannon also acknowledged that the alt-right movement, which Breitbart champions, has appeal to white supremacists and anti-Semites, according to an interview he gave to liberal magazine Mother Jones at this year’s Conservative Political Action Conference.
"Are there anti-Semitic people involved in the alt-right? Absolutely,” Bannon said. “Are there racist people involved in the alt-right? Absolutely. But I don't believe that the movement overall is anti-Semitic."
“Bitch Slap the Republican Party”
Bannon, speaking in support of the Tea Party, said in a 2010 interview on Political Vindication Radio that what supporters “need to do is bitch slap the Republican party.”
“I’m a Leninist,” Bannon reportedly told a Daily Beast journalist at a book party in 2014, referring to the revolutionary Russian communist leader. “Lenin wanted to destroy the state, and that’s my goal too. I want to bring everything crashing down, and destroy all of today’s establishment.”
“The Fight Club”
“We call ourselves ‘the Fight Club.’ You don’t come to us for warm and fuzzy,” said Bannon in the Washington Post story. “We think of ourselves as virulently anti-establishment, particularly ‘anti-’ the permanent political class.”
Chorus of Critics...and Defenders
"It is a sad day when a man who presided over the premier website of the Alt Right, a loose-knit group of white nationalists and unabashed anti-Semites and racists - is slated to be a senior staff member in the 'people's house,' said the group's CEO, Jonathan Greenblatt. "We call on President-elect Trump to appoint and nominate Americans committed to the well-being of all our country's people and who exemplify the values of pluralism and tolerance that makes our country great."
Rep. Adam Schiff, of California, called the move "alarming."
And outgoing, longtime Nevada Sen. Harry Reid expressed his ire over the decision.
“So far rather than healing these wrongs, Trump’s actions have deepened them," he said on the Senate floor Tuesday. "In his first official act he appointed a man supported as a champion of white supremacy as his chief strategist in the White House.
“If Trump is serious about unity, the first thing he should do is rescind his appointment of Steve Bannon. Rescind it. Don' t do it. Think about this. Don't do it.”
But many have come to Bannon's defense.
"I see where the outrage is and that doesn't surprise me. Same people who are trying to get past the election results," Trump campaign manager Kellyanne Conway said in Washington, DC today. "Steve Bannon is a Georgetown Harvard MBA grad, a former naval officer, a former Goldman Sachs vice president and really the general, the field general in our successful campaign effort -- a brilliant tactician and serves president elect Donald Trump very well."
Trump's Chief of Staff, Reince Priebus, called Bannon a "very, very smart person."
"I don't know where they're coming from," he said of the critics, on ABC's "Good Morning America." "That's not the Steve Bannon that I know."
Editor's Note: A previous version of this story referred to Steve Bannon as the executive chairman of Breitbart. He is the former executive chairman.