The feud between late-night hosts David Letterman and Jay Leno has been well documented, but the new biography Letterman: The Last Giant of Late Night by Jason Zinoman (obtained by PEOPLE) reveals more details surrounding the legendary host’s competitive and angsty nature.
“Letterman assumed one day he would get a call from [Johnny] Carson or the head of NBC to offer him the job [as host of The Tonight Show]. It never happened,” writes Zinoman. “Rick Ludwin, head of late-night programming at NBC, respected Letterman as a great entertainer but was skeptical that he could draw the broad swath of viewers that made up the Tonight Show audience. He also saw Letterman as difficult to deal with. Whereas Leno was friendly and approachable, Letterman was distant, even hostile.”
Leno’s accession into Carson’s seat on The Tonight Show in 1991 was helped along by Letterman‘s history of mocking his bosses on air (he once smashed a crystal decanter that NBC president Warren Littlefield sent him as a present), Zinoman writes. When Letterman learned he didn’t get the gig, he blamed Littlefield.
“I decided that I didn’t like Warren Littlefield because I didn’t get The Tonight Show,” Letterman said to Zinoman. “I blamed the whole thing on him. Rather than accept responsibility myself, I decided ‘I’ll blame somebody else…’ At the time I was up to my nose in ‘God dammit!’ “
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He also held his old manager, Jack Rollins, responsible. But, he admitted to Zinoman, “That might not have been fair.”
Leno may have gotten the gig, but his predecessor preferred Letterman. Leaving no doubt as to who was his favorite comedic son, Johnny Carson visited Late Night after the transition was announced.
“How pissed off are you?” he asked Letterman, which became one of the most memorable lines from his visit.
With Leno as the new host, Late Night and The Tonight Show were soon immersed in a ratings war.
“Leno’s ‘Tonight’ routinely beat Letterman in the ratings for the vast majority of the time they went head-to-head. But Leno was never a critical darling,” wrote pop-culture expert Scoot Collins. “From the time he started in late-night on NBC in the early 1980s, Letterman was considered an innovator.”
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According to the book, one of the most meaningful signs of success was when Carson made a second appearance on Late Night nine years after his first appearance. He never visited Leno on air.
Despite the love coming in from Carson and critics, Zinoman writes that success wasn’t guaranteed to make Letterman happy.
“Everyone is born with an emotional thermostat,” writer Steve Young said to Zinoman. “You can nudge it up and down, but it will always revert to its natural setting. His was that he was never truly comfortable unless he was seething with unhappiness at something.”
In an interesting twist, Letterman left Late Night two months after Leno departed from The Tonight Show.
“Once Jay left, I knew I had to get out,” said Letterman to Zinoman about the decision to retire. “I was already the old guy.”
Letterman: The Last Giant of Late Night releases on April 11.