Rupert Murdoch’s Fox News has grown steadily to become one of the most influential right-wing media voices in the US since it first aired on 7 October 1996.

Known for its unabashed Republican bias, pro-Donald Trump rhetoric, blurring of fact and opinion, flashy graphics and pairing of stentorian middle-aged men with steely blondes, the channel caters expertly to white Middle America’s anxieties and grievances about the state of the nation.

The network recently altered its slogan to “Real news. Real honest opinion”, replacing “Fair and balanced”, an implicit criticism of its rivals it was having increasing trouble living up to.

Fox News’ origins can be traced back to the mid-1980s, when the Australian-American media tycoon bought his stake in 20th Century Fox and a portfolio of six Metromedia local television stations broadcasting to America’s 10 biggest markets, including New York, Los Angeles, Washington, DC, and Dallas.

Uniting his assets under a new network, the Fox Broadcasting Company, Mr Murdoch’s stations initially paid out for CNN’s news feed at considerable expense.

One of its earliest original prime-time successes was the syndicated tabloid gossip show A Current Affair fronted by, among others, Steve Dunleavy, who presented himself as a hard-boiled newsman in a trenchcoat and helped set the mould for future silver Foxes like Bill O’Reilly and Sean Hannity.

By 1992, Mr Murdoch had decided his stations should broadcast their own news and flew in Andrew Neil, the editor of his Sunday Times and chairman of Sky TV, to mastermind what would become Fox News. Acquiring the rights to the NFL in 1993, the mogul envisioned an hour-long news programme to follow its coverage and take on rival CBS’s 60 Minutes.

It was at this point that Mr Murdoch drafted in political consultant and CNBC president Roger Ailes to run the show.

Rolling Stone’s Tim Dickinson summarises Ailes’ early achievements as a Republican fixer as follows: “[He] repackaged Richard Nixon for television in 1968, papered over Ronald Reagan’s budding Alzheimer’s in 1984, shamelessly stoked racial fears to elect George HW Bush in 1988, and waged a secret campaign on behalf of Big Tobacco to derail health care reform in 1993.”

“The Chairman”, who died in 2017 not long after being run out of the company after a slew of sexual misconduct allegations were made against him, served as CEO of Fox News from its inception in 1996 and as chairman, having ousted Mr Murdoch’s own son Lachlan, from 2005.

A Hitchcockian figure likened to a cross between “Don Rickles and Don Corleone” by one former deputy, Ailes is credited with conceiving Fox’s populist approach, appealing directly to the conservative Everyman.

Fox News made its intentions clear from the get-go, its anchors interviewing Israeli prime minister Benjamin Netanyahu, Nation of Islam leader Louis Farrakhan and Republican presidential candidate Bob Dole on its first day of broadcasting.

Fox had arrived on the scene just in time to join the emerging 24-hour rolling news cycle and make hay from Monica Lewinsky and the Bill Clinton impeachment. “Monica was a news channel’s dream come true,” executive John Moody would later reflect. “Their dream was my nightmare,” she countered in a New York Times editorial last year. “My character, my looks and my life were picked apart mercilessly. Truth and fiction mixed at random in the service of higher ratings.”

Under Alies’ guidance, Fox also used bolshy opinion shows to create compelling, urgent TV, typically centred around its star signings like The O’Reilly Factor, The Crier Report hosted by Catherine Crier and Hannity & Colmes, hosted by its longest-lasting big beast and token liberal Alan Colmes.

O’Reilly, Hannity and opinion editor Bill Shine formed a trio of tough Irish-American Catholics who together shaped the tone for which Fox has become known and which was so superbly sent up by Stephen Colbert in Republican hawk mode: pugnacious, patriotic and scornful of lily-livered Democrats.

In 2000, Fox News flexed its muscles for the first time by playing a huge role in the election of George W Bush. While the Republican candidate also had the crucial backing of other all-important right-wing influencers like the National Rifle Association, one study by the University of California found that he enjoyed an average boost of 200,000 votes in areas where voters had access to its programming.

The horror of 9/11 saw Fox News secure a huge ratings hike and innovate by introducing the news ticker running along the bottom of the screen to keep up with the flow of breaking developments and new information as the day unfolded – a device that has now become a staple of rolling TV news. The subsequent Iraq War, Hurricane Katrina and Boston Marathon bombing all likewise saw a marked up-tick in audience figures, indicating an American surge to the right in times of national crisis.

Fox’s relentless spinning against the Obama administration by the likes of Hannity and Glenn Beck led the then president to shun the network entirely and sparked a war of words with his fiery press secretary, Rahm Emmanuel. Senior counsel David Axelrod met privately with Ailes to discuss what could be done to soothe relations.

This was a moment that saw Fox News inspire the Tea Party grassroots movement and in which one poll concluded its audience was the least well-informed in the country. In 2011, Fox viewers were 12 per cent more likely to believe that a federal stimulus package would mean job losses, 17 per cent more likely to believe that Muslims wanted to establish the rule of Shariah law in the US, 30 per cent more likely to think scientists disputed global warming and 31 more likely to believe Barack Obama was born in Kenya.

Under President Trump, Fox News is having a field day. The billionaire businessman adores its morning show, Fox & Friends, so much that many are worried about its influence on his decision-making. He memorably called in on his wife Melania’s birthday to give an interview so rambling its hosts appeared visibly uncomfortable and is said to speak with Hannity on a nightly basis. In return, Fox has regularly called for FBI special counsel Robert Mueller, investigating the president’s ties to Russian election meddling, to be sacked.

The network has been heavily criticised for the apparent hypocrisy of its coverage of the sexual harassment scandals enveloping high-profile celebrities like Harvey Weinstein, Louis CK and others given the alleged indiscretions of Ailes, O’Reilly, Eric Bolling and other senior executives within its ranks. Hannity controversially contested the allegations against defeated Alabama senate candidate Roy Moore while Tucker Carlson and Laura Ingraham challenged The Washington Post on its coverage of the same scandal.

Ingraham also caused offence and was boycotted by 27 sponsors after attacking David Hogg, 17, a survivor of the Marjory Stoneman Douglas high school massacre in Parkland, Florida, when he campaigned for tighter gun control legislation.

Anchor Shepard Smith meanwhile angered his own side and risked alienating viewers by debunking a report on a uranium “scandal” the network was determined to tie to Hillary Clinton.

Fox News nevertheless goes from strength to strength and is about to launch a new streaming service.

David Folkenflik neatly outlines the network’s influence in his book Murdoch’s World: The Last of the Great Media Empires (2013): “No other news organisation has done more in recent years to reshape [the] terrain than Fox. Just about every news organisation either mimics or reacts against the way Fox presents the news and the values it represents.”

A new movie about Ailes’ rise and fall, directed by Jay Roach and featuring Charlize Theron as anchor Megyn Kelly, appears to be the only dark cloud on the horizon of an agenda-setting news network Tim Dickinson has ominously described as “one of the most powerful political machines in American history”.