The decision to let Mr. Carlson go was made on Friday night by Lachlan Murdoch, the chief executive of Fox Corporation, and Suzanne Scott, chief executive of Fox News Media, according to a person briefed on the move. Mr. Carlson was informed on Monday morning by Ms. Scott, another person briefed on the move said.

Mr. Carlson’s program became a must-watch for conservatives during the presidency of Donald J. Trump, an ideological ally and occasional confidant whose rise as a political force was fueled by the same populist, culture war grievances that made Mr. Carlson a star.

His departure ends a rapid and scandal-scarred rise at the conservative news and opinion channel, where he was promoted to the prime-time lineup in early 2017 after Mr. Trump’s inauguration and quickly emerged as one of Fox’s biggest names.

Few other conservative commentators anywhere — on television, talk radio or the internet — had both the relationship with Mr. Trump and the ability to sway his thinking, even if only fleetingly, and the power to speak directly to the anxieties of the former president’s followers.

But the power that Mr. Carlson, 53, wielded outside Fox News could not insulate him from a growing list of troubles inside the network related to his conduct on and off the air, some of which had been grating on Mr. Murdoch and his father, Rupert Murdoch, the chairman of Fox Corporation, who co-founded the network in 1996, according to the two people with knowledge of the company’s decision.

The host, a polarizing and unpopular figure at the network outside of his own staff, was exposed as part of a defamation lawsuit by Dominion Voting Systems as a bully who denigrated colleagues and sources, often in profane and sexist language, and called for the firing of Fox journalists whose coverage he disliked. He has also drawn condemnation from the right and left for his role in fostering a revisionist account of the assault on the United States Capitol on Jan. 6, 2021.

No one so high-profile has exited Fox News so suddenly and unexpectedly since the tumultuous period at the network in 2016 and 2017, when Roger Ailes, the chief executive, and Bill O’Reilly, Fox’s biggest prime-time star, were fired, in their cases for sexual misconduct.

One early point of contention was Mr. Carlson’s 2021 documentary, “Patriot Purge,” which advanced the conspiracy theory that the attack that day was a so-called false flag operation designed to discredit the former president and his political movement. Lachlan Murdoch was said to have been caught off guard by the program, which also led two conservative Fox News contributors to quit in protest, Jonah Goldberg and Stephen Hayes.

In March, Mr. Carlson edited down tens of thousands of hours of footage from the attack given to him by Speaker Kevin McCarthy and used them to falsely portray the rioters as people Mr. Carlson called “mostly peaceful” onlookers who had innocently ambled into the Capitol. The broadcast drew a rebuke from Senator Mitch McConnell, who is a friend of Rupert Murdoch’s and said Mr. Carlson had drawn “offensive and misleading conclusions.”

In recent weeks, however, tumult unfolding off the air was what contributed to Mr. Carlson’s ouster. He was set to be a star witness in the trial of Dominion’s billion-dollar defamation lawsuit against Fox News until the network abruptly settled for $787.5 million last week.

And late last month, one of his former producers filed a lawsuit against Fox and Mr. Carlson, claiming that the host ran a toxic workplace. The producer, Abby Grossberg, said in her complaint that she endured an environment “where unprofessionalism reigned supreme, and the staff’s distaste and disdain for women infiltrated almost every workday decision.” She also accused her former colleagues on “Tucker Carlson Tonight” of making antisemitic remarks and frequently speaking crudely and disparagingly about women.

On Monday, Fox offered a terse statement of gratitude in making the announcement of Mr. Carlson’s departure but did not offer any explanation. “Fox News Media and Tucker Carlson have agreed to part ways. We thank him for his service to the network as a host and prior to that as a contributor,” the network statement said.

Mr. Carlson did not respond to requests for comment on Monday.

The Fox News host Harris Faulkner said on air Monday that starting that evening, an interim show, “Fox News Tonight,” would fill the 8 p.m. hour “with rotating Fox News personalities until a new host is named.”

The ouster was an ignominious turn in the career of a man had once been rumored as a possible presidential contender in Republican circles. When Mr. Trump was in the White House, Mr. Carlson had his ear when he wanted it. And long before he became a Covid vaccine skeptic — Mr. Carlson’s political persona often shifted with the whims of his audience — he traveled to Mar-a-Lago, Mr. Trump’s Florida estate, in March 2020 to personally encourage the president to take the coronavirus more seriously. He explained to Vanity Fair that at the time, he felt “a moral obligation to be useful in whatever small way I could.”

Both Mr. Trump and Mr. Carlson helped push far-right positions on issues like border policy and race relations into the Republican mainstream, and both relished antagonizing their political opponents with audacious and often untrue attacks.

Mr. Carlson warned his viewers that they were under assault from liberal elites and unchecked immigration, borrowing some of his central themes from the white nationalist and far-right web and polishing them up for a more mainstream audience. When he feared that Mr. Trump was wavering on his campaign promises — to enact harsh policies to deter and expel migrants and reduce American entanglements in foreign conflicts, for instance — he made his concerns known on his show, which typically drew about three million viewers a night.

When Fox launched a streaming network, Fox Nation, to draw more revenue from its most loyal fans, it was Mr. Carlson who became the new platform’s top personality, with a thrice-weekly talk show and periodic documentaries that doubled down on his themes of duplicitous elites and race-obsessed liberals.

At his height within Fox, he defied the network’s senior leadership while cultivating the impression among colleagues that he was cozy with the Murdoch family, particularly the Fox chief, Lachlan Murdoch. But in his sworn deposition as part of the Dominion suit, Mr. Carlson said the two men were not especially close. Asked how often he communicated with Lachlan Murdoch, Mr. Carlson replied, “Rarely.” He added, “It’s not on a weekly basis or even a monthly basis.”

The Dominion case exposed Mr. Carlson as someone whose polemical pro-Trump persona didn’t always match what he said privately. As he told his viewers after the 2020 election that they were right to have doubts about the credibility of the vote counting, he was telling his producers the opposite.

His private messages with members of his staff — in which they denigrated Mr. Trump and his legal advisers after the 2020 election in vulgar and sexist terms — were disclosed as part of Dominion’s defamation lawsuit against Fox. In one exchange with staff, Mr. Carlson texted about Mr. Trump, “I hate him passionately.” In another, he labeled Mr. Trump — whom he often praised on his show — “a demonic force, a destroyer.”

In the lawsuit recently filed by Ms. Grossberg, in which she claims that she was coerced by Fox’s lawyers into providing a misleading deposition in the Dominion case, she accuses Mr. Carlson of presiding over a misogynistic and discriminatory workplace culture.

Ms. Grossberg said in the lawsuit, which was filed in March, that on her first day working for Mr. Carlson, she discovered the work space was decorated with large pictures of Speaker Nancy Pelosi wearing a plunging swimsuit. .

“Mr. Carlson’s derogatory comments towards women, and his disdain for those who dare to object to such misogyny, is well known” on the set of his show, the lawsuit said.

A lawyer for Ms. Grossberg, Parisis G. Filippatos, said on Monday that Ms. Grossberg had almost 90 recordings from her time at Fox that bore out her claims of a hostile work culture, and bolstered the case that Fox had aired lies about voter fraud.

Fox has said it would fight Ms. Grossberg’s claims. She was fired after filing the lawsuit in New York, and another one, against the company, in Delaware.

Justin Wells, the senior executive producer of “Tucker Carlson Tonight,” is also no longer employed by Fox News, according to two people with knowledge of the decision inside the network. Mr. Wells had worked closely alongside Mr. Carlson since his prime-time show began in 2016.

In recent years, Mr. Carlson led people to believe that he was untouchable. Last year, in an interview with the media outlet Semafor, he boasted that he operated with virtual autonomy at Fox. “I don’t clear anything with anybody. I file my script late,” Mr. Carlson said.

He is not the first star Fox personality to leave the network after developing a huge following. In 2011, the network pushed out Glenn Beck, the Tea Party megastar whose anti-Obama rants made his show one of the most popular in Fox News history. Two years later, Fox parted ways with Sarah Palin, the former Alaska governor.

Fox executives said at the time that one factor more than anything else led to the departures: No one person is bigger than the network.

Nicholas Confessore and Jim Rutenberg contributed reporting.