Image copyright Reuters Image caption After Mr Bannon left the White House, schisms started to show

Steve Bannon - the driving force behind the right-wing Breitbart News website who later became Donald Trump's chief strategist - has been charged with fraud three years after leaving the White House.

He is alleged to have been part of a group who defrauded hundreds of thousands of donors who thought they were contributing money to build a wall on the US-Mexico border to block illegal immigration.

During the 2016 presidential campaign and in the White House, Mr Bannon had a direct line to President Trump - who seemed to be his ideological soulmate. But that came to an end when he left his post in August 2017 as their relationship began to cool.

Since then the former Hollywood producer has campaigned for a privately-funded wall on the border - making Mr Trump's signature 2016 campaign promise his personal mission.

But in August 2020, less than three months before an election deciding whether Mr Trump gets a second term, prosecutors in New York indicted and arrested him. He pleaded not guilty.

'Bannon the Barbarian'

Mr Bannon left the White House in August 2017 after months of reported power struggles with Mr Trump's son-in-law and senior adviser, Jared Kushner, as well as other high-level Trump advisors.

Mr Trump had also reportedly grown weary of press leaks and of Mr Bannon taking credit for his election victory.

Media playback is unsupported on your device Media caption White House Press Secretary Sarah Sanders explains why Mr Trump rounded on his former adviser Steve Bannon

Mr Bannon headed back to Breitbart, vowing to wage war on the president's opponents, saying: "I've got my hands back on my weapons... It's Bannon the Barbarian."

But the schisms soon started to show.

Mr Bannon said Mr Trump's firing of the FBI's director had been the biggest mistake in "modern political history".

He also defied the president by championing a controversial Alabama Senate candidate who crashed to a humiliating defeat against a Democrat.

Image copyright Getty Images Image caption Republican Roy Moore (centre) was backed by Mr Bannon but lost a special election

The divide grew when Mr Bannon was quoted in a book as describing a meeting between Mr Trump's son and a group of Russians - an encounter that featured prominently in Mr Trump's impeachment trial - as "treasonous".

"Steve Bannon has nothing to do with me or my presidency. When he was fired, he not only lost his job, he lost his mind," Mr Trump said in a statement.

'Sloppy Steve'

Mr Bannon swiftly recanted, but the damage was done. One of Breitbart News's major financial backers, Rebekah Mercer, cut him loose and days later he stepped down.

In January 2018, Mr Trump took to Twitter to cheer the decision with a new moniker for his old ally.

"The Mercer Family recently dumped the leaker known as Sloppy Steve Bannon. Smart!" Mr Trump wrote.

But by August 2019, wounds appeared to have healed. Mr Trump described Steve Bannon in a tweet as "one of my best pupils" and "still a giant Trump fan".

Image copyright Getty Images Image caption Mr Bannon, pictured at President Trump's inauguration in 2017

'We Build the Wall'

In August 2020, Mr Bannon, 66, was indicted for conspiracy to commit wire fraud and conspiracy to commit money laundering along with three other alleged co-conspirators.

The "We Build the Wall" project "defrauded hundreds of thousands of donors, capitalising on their interest in funding a border wall to raise millions of dollars, under the false pretence that all of that money would be spent on construction", said Audrey Strauss, the acting US Attorney for the Southern District of New York.

Mr Bannon had received more than $1m through a non-profit organisation he controlled, at least some of which he used to "cover hundreds of thousands of dollars" worth of personal expenses, she alleged.

Meanwhile, Brian Kolfage - founder of "We Build the Wall" - "covertly took" $350,000 for his personal use, prosecutors alleged.

From the beginning, the project had been mired in controversy with critics saying the three miles of wall that We Build the Wall helped construct was too close to the Rio Grande river. As a result, it quickly suffered from severe erosion that threatened its stability.

Image copyright We Build the Wall Image caption The campaign exhorted individuals to "buy a brick"

The project had been sparked by a 2018 online campaign after Congress refused to approve funds requested by Mr Trump to build a border wall.

After experts found evidence of severe erosion, Mr Trump condemned the group, tweeting in July 2020: "I disagreed with doing this very small (tiny) section of wall, in a tricky area, by a private group which raised money by ads.

"It was only done to make me look bad, and perhsps [sic] it now doesn't even work."

The Hollywood years

Born in Virginia in 1953, Mr Bannon spent four years in the navy before completing an MBA at Harvard.

He went into investment banking and after a spell with Goldman Sachs moved into media financing, helping to get the comedy show Seinfeld, among others, off the ground.

He shifted into film production, working in Hollywood before branching out into independent political documentary-making, paying homage to former US President Ronald Reagan, former Alaska Governor Sarah Palin and the Tea Party movement.

Through this work he met Andrew Breitbart, a staunchly conservative media entrepreneur who wanted to create a site that challenged what he saw as liberal-dominated mainstream media.

When Breitbart died of a heart attack in 2012, Mr Bannon took over as head of Breitbart News and drove it forward.

Image copyright Breitbart Image caption One of Breitbart's many controversial headlines

The site positioned itself as a populist, bellicose, conspiracy-tinged outlet for right-wing Americans disillusioned with mainstream politicians.

During the 2016 election campaign, the site was fulsome in its support of Donald Trump. At the same time, Democrats and civil rights groups were accusing Mr Bannon and his media outlet of allying themselves with white nationalists.

Mr Trump had appointed Mr Bannon as his campaign CEO in August 2016 and, following his victory, handed him the key White House role.

Mr Bannon's troubles in 2017 and 2018 delighted the Republican mainstream, which had been repeatedly assailed by Breitbart.

But the banishing of the conservative, bare-knuckle fighter then raised a big question: would he go quietly?

Some might have expected a return to the headlines ahead of the 2020 vote. But few will have predicted Mr Bannon's arrest.