Roger Ailes, former chief executive of Fox News Channel, has died at age 77, Fox News said on Thursday.

Ailes resigned from Fox last July following allegations of sexual harassment, marking an abrupt end to his 20-year reign over America's most lucrative and powerful cable news channel for conservatives.

Fox News is owned by Rupert Murdoch's Twenty-First Century Fox Inc. Ailes received a severance package of about $40 million when he left Fox News, according to a source familiar with the situation, and went on to serve as an informal adviser to Murdoch.

“Today America lost one of its great patriotic warriors," Fox News host Sean Hannity said in a statement read on the channel on Thursday. "For decades, RA (Roger Ailes) has impacted American politics and media. He has dramatically and forever changed the political and the media landscape single-handedly for the better."

Brian Kilmeade, another Fox News host, said on the channel that Ailes “helped build Fox News Channel into the powerhouse it is today.”

Ailes' widow, Elizabeth Ailes, confirmed his death in a statement on the Fox News website.

"I am profoundly sad and heartbroken to report that my husband, Roger Ailes, passed away this morning," she wrote.

Neither his wife nor Fox released any details on the circumstances of Ailes' death. He suffered from hemophilia, according to a source familiar with the matter.

Gabriel Sherman, a reporter who wrote a biography of Ailes, said on Twitter that Ailes died after suffering a blood clot after falling in Palm Beach, Florida, citing two family friends. Reuters could not immediately confirm Sherman's report.

Twenty-First Century Fox had no immediate comment.

CLEAR CONSERVATIVE VISION

As founder, chairman and chief executive officer of Fox News, Ailes became one of the most influential figures in the Republican Party, and the network was integral to President Donald Trump's successful run for the White House in 2016.

From the start, Ailes had a clear conservative vision of what he wanted Fox to be as he took the network to the top of the cable news ratings and made it a major profit center for Rupert Murdoch's Twenty-First Century Fox Inc media empire.

But accusations of Ailes' treatment of women would be his downfall.

In July 2016, Gretchen Carlson, a former Miss America who appeared on the popular "Fox and Friends" morning program before being given her own show, sued him. She said he had made sexual advances toward her and then hurt her career in retaliation after she rejected him.

Two weeks later, Ailes was ousted from the network. His departure came during the Republican National Convention and at a time when the network was scoring record ratings. Shortly afterward, he began advising the Trump campaign.

Ailes had run Fox News under the slogan "fair and balanced" and conservatives found it a much-needed antidote to the perceived liberal slant of traditional media. Critics denounced it as a cynical and polarizing right-wing propaganda machine.

"He helped market a brand of pseudo-journalism that revolves basically around hate, rhetoric, divisiveness, pitting people against each other," Eric Boehlert, senior fellow at liberal media watchdog Media Matters for America, told Reuters. "That seeps into the culture and into politics."

The story of Fox News was the story of Ailes. His conservative red-white-and-blue beliefs set the narrative for the network's stories, and critics said it was difficult to determine where Ailes' agenda ended and Republican Party talking points began. No potential Republican presidential candidate stood much of a chance without Ailes' blessing.

"I want to elect the next president," he told Fox executives at a 2010 meeting, according to the 2014 biography "The Loudest Voice in the Room" by Gabriel Sherman, a writer for New York magazine.

"Ailes' power and ruthlessness ... allowed him to take over the Republican Party and mold it to fit his paranoid world view," Sherman told the Washington Post in 2016.