Moments after being convicted of contempt of Congress in July, Steve Bannon, a former media entrepreneur, naval officer, investment banker and Trump administration aide, walked out of a Washington courthouse and made a declaration that summed up what the better part of the last decade of his life had been about.

“I stand with Trump and the constitution, and I will never back off that, ever,” Bannon declared.

On Friday, a federal judge sentenced Bannon to four months in jail and a $6,500 fine, for defying a subpoena from lawmakers investigating the January 6 insurrection.

It was the latest twist in the varied career of the 68-year-old far-right provocateur.

Bannon was by Donald Trump’s side during his ascent to the White House and guided some of his most divisive moments, including his decision to ban travelers from Muslim-majority countries and his equivocation over a deadly white supremacist attack in Charlottesville, Virginia.

Bannon then met a fate common to Trump White House officials – pushed out, in his case after less than eight months and after repeatedly clashing with Jared Kushner, the president’s son-in-law and senior adviser.

But Bannon’s loyalty remained, and it paid off. On his last day in office, Trump pardoned Bannon, who had been convicted on federal fraud charges.

Now Bannon is trying to keep his freedom again. This time he can expect no presidential pardon, at least not as long as Joe Biden is in the White House. But he will remain free while appealing his sentence, his strategy, according to people close to him, to drag out the proceedings until the January 6 committee’s mandate expires at the end of this year.

“We may have lost a battle here today but we’re not going to lose this war,” Bannon said in July, after a Washington jury handed down its guilty verdict.

The son of a working-class Irish Catholic family of Democrats, Bannon grew up in Virginia, attended military prep school and spent four years in the navy before graduating with a MBA from Harvard.

He worked as an investment banker for Goldman Sachs then got into media financing, where he profited from the success of Seinfeld, one of the greatest TV comedies of all time.

It was during his time as a film producer in Hollywood that Bannon met the conservative media entrepreneur Andrew Breitbart. Bannon took over the Breitbart News website after its founder died of a heart attack in 2012. Bannon once described the outlet as the “the platform of the alt-right”, embracing the racism and antisemitism Trump would use as fuel for his electoral success four years later.

Bannon made Trump’s acquaintance in 2010, and was impressed by his stance on China and international trade. He took over as Trump campaign chair months before the election in 2016, helping hone the populist edge used to upset Hillary Clinton.

Bannon co-wrote the grim “American carnage” speech Trump gave at his inauguration and helped see through divisive opening actions including pulling out of the Paris climate accords.

Amid infighting within Trump’s inner circle of advisers, Bannon was pushed off the National Security Council by April, and out of the administration entirely by August.

Critics decry him as a nationalist and a nihilist bent more on destroying the American political system that reforming it. Bannon describes himself as a “Tea Party populist guy” and in the past has insisted that his goal is to get the Republican party to focus its policies on the American people.

“We’ve turned the Republican party into a working-class party,” he told the Guardian in 2019.

Left unsaid was Bannon’s view that Trump would be best to lead that party no matter the cost. In a recording obtained by Mother Jones, Bannon described in 2020 how the then-president planned to declare victory in his re-election campaign even before all the votes were counted.

“That’s our strategy,” Bannon said. “He’s gonna declare himself a winner. So when you wake up Wednesday morning [after election day], it’s going to be a firestorm.

“You’re going to have antifa, crazy. The media, crazy. The courts are crazy. And Trump’s gonna be sitting there mocking, tweeting shit out: ‘You lose. I’m the winner. I’m the king.’”