Stephen Bannon stepped down as chairman of Breitbart News on Tuesday, marking a stunning fall for the once high-flying populist agitator and former White House chief strategist who helped turn Breitbart into a right-wing juggernaut.



Bannon has been forced out of Breitbart a week after the publication of author Michael Wolff’s book “Fire and Fury,” in which Bannon is quoted making disparaging remarks about President Trump Donald John TrumpObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE’s family. Bannon is widely believed to be the primary source for that book, which has become a massive political headache for the White House.



In the aftermath of Bannon’s comments, Trump dramatically rebuked his former chief strategist. The president has since taken to calling Bannon “Sloppy Steve,” while the White House has sought to diminish the impact Bannon had on the campaign and as Trump’s chief strategist.



Bannon’s comments about Trump’s family also provoked a rare public rebuke from GOP mega-donor Rebekah Mercer, a Trump supporter who owns a large stake in Breitbart News and had otherwise been a staunch ally of Bannon and his political crusades.



“Steve is a valued part of our legacy, and we will always be grateful for his contributions, and what he has helped us to accomplish,” Breitbart CEO Larry Solov said in a statement posted on Breitbart’s website.



Bannon remains a hugely popular and influential figure inside the Breitbart newsroom. His departure will raise questions about the future of the news outlet as it seeks to move on without the man who acted as its public figurehead and editorial director since 2012, after the death of Breitbart founder Andrew Breitbart.



“I’m proud of what the Breitbart team has accomplished in so short a period of time in building out a world-class news platform,” Bannon said in a statement.



It’s a stunning turn of events for Bannon, who once harbored ambitious plans for 2018 but has now been consigned to political irrelevancy.



Working with a pro-Trump outside group, Bannon and his allies had been planning to orchestrate primary challenges against nearly every Republican senator for reelection in 2018 in an effort to push the party further right.



Candidates once jockeyed for Bannon’s support and incumbent lawmakers feared his involvement in their primaries.



Bannon’s allies now concede that his primary effort is meaningless, since he can no longer claim to be Trump’s standard-bearer.



And now Bannon has been cut off from Breitbart, the pro-Trump outlet that he used to push his national economic populism and attack Republican leaders, who he cast as insufficiently loyal Trump and out of touch with ordinary Americans.



Bannon’s allies have said that he still plans to launch a nonprofit group called Citizens of the American Republic that those close to him say will focus on policy matters.



While Bannon can no longer rely on the Mercers for financial support, he has used his time out of the White House meeting with other wealthy donors who could back his new venture.



“He had to either give up being involved in politics or Breitbart, couldn’t do both,” one source told The Hill. “He chose politics. Him being involved in politics was interfering with Breitbart’s ability to act as a news organization.”



Indeed, Bannon’s problems began before the release of the Wolff excerpts.



Bannon went all-in for embattled GOP Senate candidate Roy Moore Roy Stewart MooreVulnerable Senate Democrat urges unity: 'Not about what side of the aisle we're on' Sessions hits back at Trump days ahead of Alabama Senate runoff Judge allows Roy Moore lawsuit over Sacha Baron Cohen prank to proceed MORE, first in the primary and then in the general election.



Bannon and his allies were flying high after Moore defeated incumbent Sen. Luther Strange Luther Johnson StrangeSessions hits back at Trump days ahead of Alabama Senate runoff The biggest political upsets of the decade State 'certificate of need' laws need to go MORE (R-Ala.) in the primary, in what was viewed at the time as a massive victory over Senate majority leader Mitch McConnell Addison (Mitch) Mitchell McConnellObama calls on Senate not to fill Ginsburg's vacancy until after election Planned Parenthood: 'The fate of our rights' depends on Ginsburg replacement Progressive group to spend M in ad campaign on Supreme Court vacancy MORE (R-Ky.) and his allies. Trump had also endorsed Strange.



Bannon stuck with Moore even after the candidate was accused ahead of the general election of molesting a young girl decades ago. He dispatched Breitbart reporters to Alabama to defend the candidate and to dig up dirt on Moore’s accusers, infuriating many Washington Republicans, who worried the efforts would tarnish the party as a whole.



Moore was defeated by Democrat Doug Jones in a race that had been expected to be an easy win for Republicans before the Moore allegations emerged.



That loss cost Bannon substantial influence. His many enemies within the GOP came out of the woodwork to demand the party cut ties with him.



On Tuesday, many of them celebrated Bannon’s demise.

Bannon now needs to divest himself entirely from Breitbart. This is a great step in the right direction and a good move for Andrew’s legacy. https://t.co/UnhHuFPhCc