Authorities in Florida are saying Ailes died of bleeding on the brain caused by an earlier fall at home.
Fox News executive chairman Rupert Murdoch issued a statement saying he was "shocked and grieved" by his passing.
In a tweet Thursday, Bush wrote, "not sure I would have been President w/o his great talent, loyal help".
Mr Ailes became the founding boss of Fox News in 1996, turning it into a profits and ratings powerhouse. He was beloved by many in the right-wing political sphere for bringing reactionary conservative thought to the mainstream, and he was also celebrated for his business acumen in turning Fox News into the top-rated cable news network.
By mid-2016 Ailes still ruled supreme as he prepared to celebrate Fox News' 20th anniversary.More news: Mayhem rages in west Venezuela; Capriles blocked from U.N. trip
A longtime confident of media titan Rupert Murdoch, Ailes was seen as a central figure in the conservative U.S. political movement, who stood down at Fox in July previous year after a sexual harassment lawsuit from former news host Gretchen Carlson.
Carlson said there had been at least six instances when Ailes talked about her body, intimidated her or used demeaning language.
With high-tech production values and cheeky slogans like "Fair and Balanced" and "We Report, You Decide", Fox News quickly challenged what Ailes viewed as a liberal-leaning mainstream media. The announcement was made on July 21.
Before Carlson's bombshell legal action, Fox's roaring success and enormous earnings (with some estimates that it accounted for almost a quarter of the parent company's profits) insulated Ailes from any suspicion as well as from his past scrapes with the Murdoch sons over whom he would report to. Charges that he vehemently denied. Concluding that viewers would never warm to Nixon, nor would the media establishment, Ailes struck a winning formula by packaging him in comfortably staged TV town-hall meetings as a man whose intelligence the audience would respect.
"Ailes was a brilliant TV executive who saw an opportunity two decades ago to build a conservative news source and seized it, and then with his singular and rigid focus he succeeded beyond even his wildest dreams".
Ailes was born in Warren, Ohio, and studied radio and television production at Ohio University, according to Fox News.More news: Kane scores four and Son hits double as Tottenham rout Leicester
"Just the contribution he made to politics and the contribution he made to television news its unparalled, both of those", Jarvis said.
He played a role in Mr Nixon's successful campaign, as well as for other Republican presidents Ronald Reagan and George Bush Snr.
Sean Hannity, a prime time host and longtime face of the network, said on Twitter: "Today America lost one of its great patriotic warriors". Bill O'Reilly, who was also accused of sexual harassment by multiple women, followed Ailes out the door a few months later. After starting his media consultancy in 1968, he also produced a handful of Broadway shows, including 1973's "The Hot L Baltimore", which ran for three years at the Circle in the Square.
After he resigned from Fox News, Ailes reportedly returned to politics. It was ironic, then, that Ailes was ousted only hours before Trump accepted the GOP nomination for which Fox had helped pave the way.More news: Clinical KKR Beat Sunrisers by 7 Wickets to Enter Qualifier 2
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