Championed by conservatives as a visionary, reviled by liberals as a menace, Fox News founder Roger Ailes re-shaped US television news and helped to craft a conservative populism that ultimately gave rise to Donald Trump.
The titles of just two Ailes biographies, "The Loudest Voice in the Room" and "Dark Genius" hint to the outsized and controversial nature of his legacy after a five-decade career in television and politics.
When Fox News was created in 1996, Australian-born tycoon Rupert Murdoch provided the money and Ailes the vision. A broadcast entrepreneur, it was Ailes who understood perfectly how to blend entertainment with conservative politics.
"Either this man is crazy or he has the biggest set of balls I've ever seen," Murdoch is widely quoted as having said of first meeting Ailes.
With the slogan "fair and balanced," Fox presented itself as a potent counterweight to perceived liberal bias of mainstream US media, and quickly rode the wave of anger over Bill Clinton's affair with a White House intern.
Under Republican president George W. Bush, it championed patriotism, and the US invasions of Afghanistan and Iraq in the wake of the September 11, 2001 attacks.
Under Barack Obama, it became a soap box for right-wing Republicans, giving extensive air to the myth that America's first black president was not born in the United States and denying that human activity played a role in climate change.
While Ailes was forced out last year in a blaze of sexual harassment allegations, which he denied, Fox News today is the most watched cable news network in America, a powerhouse of the right and the bete noire of Democratic coastal elites.
"Ailes, apart from a few presidents and maybe a scattered number of other people, was one of the most important figures in American political history in the last half century," says David Greenberg, professor of history, journalism and media studies at Rutgers University.
"He really did as much as anyone to redefine the Republican Party as a party of cultural populism ... making resentment of the media, resentment of elites, resentment of liberals who were soft on crime and soft on national security central to what the Republican Party was about," Greenberg told AFP.
- 'Trump logical conclusion' -
Born into a blue collar family in Ohio, he began his career in daytime television, learning the art of manufacturing good entertainment before moving into politics, becoming an advisor to Richard Nixon, Ronald Reagan and George H.W. Bush.
"With Ailes, you have this rare convergence of someone who is equally savvy in media style as they are in understanding the narratives and themes of American politics," says Reece Peck, an assistant professor at College of Staten Island who is writing a book about Fox News. "Usually you only have one or the other," he told AFP.
But liberals rubbish the idea that Fox was a sincere counterpoint to a mainstream liberal media, accusing the channel of running a ruthlessly partisan operation.
"Fox News often operates almost as either the research arm or the communications arm of the Republican Party," Anita Dunn, communications director in the Obama White House, told CNN in 2009.
A Pew Research survey from 2012 found that while CNN and MSNBC were watched by a more mixed audience, 60 percent of Fox News viewers called themselves conservative.
"Avowedly partisan and ideological news has made it possible for a lot of Americans to opt out of the common discourse and the common fund of information about politics that governed a political life for so long," said Greenberg.
But if Fox was reluctant to embrace Trump during the antagonistic Republican presidential primary, the channel jumped on board after he clinched the nomination. If nothing else, its audience was a captive Trump market.
The marriage of politics and entertainment that Ailes orchestrated at Fox became an effective tool for political communication, and one that Trump also deftly put to use in his once improbable bid for the White House.
"Trump is kind of the logical conclusion of a long-term trend of entertainment-izing of American politics. And Ailes had a major role in creating that kind of political culture," says Peck, an assistant professor of media culture.
It was a role that Murdoch recognized in paying tribute to his friend Thursday.
"A brilliant broadcaster, Roger played a huge role in shaping America's media over the last 30 years," said the Fox News Channel executive chairman. "Roger and I shared a big idea which he executed in a way no one else could have."