Fox News tapped veteran journalist and commentator Tucker Carlson to replace Megyn Kelly in one of its most prominent time slots, underscoring that the cable news network has no intention of moving away from its conservative roots.

Mr. Carlson, who had recently begun hosting a 7 p.m. show on Fox News, will take over the 9 p.m. time slot from Ms. Kelly, a star anchor who announced this week that she is leaving for NBC News after a 12-year career at Fox. Mr. Carlson takes over on Monday.

The 47-year-old rose to national prominence as the co-host of the CNN show “Crossfire,” where he represented the political right until the show’s cancellation in 2005. He has written for a variety of media outlets over the years and co-founded the conservative site the Daily Caller.

Picking an established anchor on its own network was a safe move for Fox News. Mr. Carlson has done well at 7 p.m. since replacing Greta Van Susteren in November. His average audience of 2.8 million viewers beats both CNN and MSNBC combined.

MSNBC announced Thursday that Ms. Van Susteren will be joining the network to host “For the Record with Greta,” providing news coverage and analysis at 6 p.m. on weeknights. Her show also starts on Monday.


Mr. Carlson’s early success as her replacement persuaded Rupert Murdoch, the chairman of Fox News and co-executive chairman of parent company 21st Century Fox, to elevate him to a more powerful perch at the top-rated news channel.

Fox News star anchor Megyn Kelly is leaving the cable network to join NBC News. The announcement ends months of intense speculation over the future of "The Kelly File" host. Photo: Associated Press

“In less than two months, Tucker has taken cable news by storm with his spirited interviews and consistently strong performance,” Mr. Murdoch said in a statement. “Viewers have overwhelmingly responded to the show and we look forward to him being a part of Fox News’ powerful primetime lineup.”

Although Mr. Murdoch hasn’t been in Fox News’ New York headquarters this week, he was calling the shots on how to replace Ms. Kelly, a person familiar with the matter said.

21st Century Fox and Wall Street Journal-parent News Corp share common ownership.


Fox entered a new era last summer with the departure of longtime network boss Roger Ailes. He resigned after he was sued by former anchor Gretchen Carlson for sexual harassment. Her suit was settled by 21st Century Fox, as were similar accusations from other women that emerged during an internal investigation. Mr. Ailes has denied the allegations.

His exit had sparked speculation in the media world that Fox might reorient its shows more toward the political center or introduce more hard news. But Mr. Murdoch has made clear he has no intentions of changing the editorial tone of Fox’s prime time lineup, calling it “business suicide” in an October interview.

The appointment of Mr. Carlson shows that Fox News is, indeed, sticking to its traditional formula. In a prime-time lineup that also features Bill O’Reilly and Sean Hannity, Ms. Kelly was widely viewed as the least ideological and most willing to take on Republicans.

Mr. Carlson wasn’t a big booster of Donald Trump during the 2016 campaign, but he hasn’t had run-ins with the president-elect of the sort Ms. Kelly did. Her questioning of Mr. Trump during at a Republican primary debate about his treatment of women helped propel her to greater prominence but created friction with Mr. Trump’s supporters, media observers say.


In a Jan. 2016 column for Politico, Mr. Carlson wrote that while Mr. Trump “might not be my first choice” for president and was an “imperfect candidate” his candidacy had something to teach Republicans.

Mr. Carlson ventured into TV in 2000, joining CNN. He hosted a show on MSNBC from 2005 to 2008 and hosted a PBS show. As co-host of “Crossfire” he had a memorable on-air battle with former “Daily Show” host Jon Stewart—who attacked “Crossfire” as coarsening political discourse.

The moving of Mr. Carlson to Ms. Kelly’s time slot could open Fox News up to criticism that it now has no female anchors in the 8 p.m. to 11 p.m. window.

The network is giving Mr. Carlson’s current 7 p.m. home to daytime news anchor Martha MacCallum, at least for the first three months of the Trump administration, with a new show called “The First 100 Days,” which will premiere on Jan. 16.


Mr. Murdoch said Ms. MacCallum has “proven to be an essential component of our news programming.”

Write to Joe Flint at joe.flint@wsj.com