The 92-year-old Australian press magnate, Rupert Murdoch, whose creation of Fox News made him a force in American politics, is stepping down as leader of both Fox’s parent company and his News Corporation press holdings.

Fox said Thursday that Mr. Murdoch would become chairman emeritus of both companies, effective at board meetings in November. His son, Lachlan, will become News Corp. chairman and continue as chief executive officer of Fox Corp.

Lachlan Murdoch said that “we are grateful that he will serve as chairman emeritus and know he will continue to provide valued counsel to both companies.”

Besides Fox News, Mr. Murdoch started the Fox broadcast network, the first to successfully challenge the Big Three of ABC, CBS and NBC, with shows like “The Simpsons.” He is owner of The Wall Street Journal and the New York Post.

He slimmed down his corporate holdings with the 2019 sale of many entertainment assets to Disney. These included film production, rights to the Marvel comics, National Geographic and the cable network FX.

Fox News Channel has profoundly influenced television and the nation’s politics since its start in 1996, making Mr. Murdoch a hero to some and pariah to others. The 24-hour network converted the power and energy of political talk radio to television. Within six years, it outrated CNN and MSNBC.

But it has been a rough year for Fox, which was forced to pay $787 million to settle a defamation lawsuit related to its coverage of false claims following the 2020 presidential election. Shortly after, Fox fired its most popular personality, Tucker Carlson.

Stock in Fox Corporation, while positive this year, began to decline early in 2022, due in part to lawsuits and investor anxiety over the loss of viewers to smaller media outlets.

Mr. Murdoch vowed in a letter to employees that he would remain engaged at Fox.

“In my new role, I can guarantee you that I will be involved every day in the contest of ideas,” Mr. Murdoch wrote. “Our companies are communities, and I will be an active member of our community. I will be watching our broadcasts with a critical eye, reading our newspapers and websites and books with much interest.”

There was no immediate word on why Mr. Murdoch’s announcement came now. Ironically, next week author and Murdoch biographer Michael Wolff is publishing a book, “The End of Fox News,” speculating on what will happen to the network when the patriarch is gone.

Mr. Murdoch and his family, particularly children James, Lachlan, Elisabeth, and Prudence, were said to be the model of the HBO show “Succession.”

He built his empire from a single newspaper at Adelaide, Australia, inherited from his father and became a multi-billionaire. Forbes estimated the Murdoch family’s net worth at roughly $19 billion in 2020.

While Mr. Murdoch never ran for political office, politicians in the United States and Britain anxiously sought his approval. He had a complicated relationship with President Trump. 

Mr. Wolff reported in 2018 that Mr. Murdoch had called Mr. Trump an “idiot,” adding an expletive for emphasis, but Fox News is built with an audience that largely admires Mr. Trump.

Fox briefly seemed to tout the candidacy of Governor DeSantis in the current election cycle, but that has faded along with Mr. DeSantis’ prospects.

For decades, Mr. Murdoch was one of the most powerful Press figures in Britain, a market he entered after buying the tabloid News of the World in 1969. He reinvigorated Britain’s stodgy newspaper scene with sex, scandal and celebrity and helped shake up television with satellite broadcaster Sky.

His clout has waned since the revelation more than a decade ago that employees of the News of the World had eavesdropped on phones and used other underhanded methods to get scoops on celebrities, politicians and royals. 

News Corporation owns the Times, Sunday Times, and Sun newspapers, but News of the World closed and Mr. Murdoch sold his 40 percent stake in Sky when he failed to get complete control of the company.

Fox News went through a series of sexual harassment scandals in the 2010s, which led to top executive Roger Ailes and prime-time personality Bill O’Reilly being pushed out. Mr. Murdoch dismissed them as isolated instances that were “largely political because we’re conservative.”

Shares of News Corporation and Fox rose Thursday in early trading.

Associated Press