On October 11, 1975, comedian George Carlin came down from the balcony in one of NBC's studios and made his way to the center of the stage. For the next three-plus minutes, he treated audiences in person and watching at home to a monologue about football and baseball. (You can watch it here.) And with that, a television franchise was born: Saturday Night Live, the iconic sketch comedy show, debuted. It's been on ever since, running for nearly 1,000 episodes over 48 seasons, earning 93 Primetime Emmys, and launching the careers of countless comedic actors.

And we probably have Johnny Carson to thank for it.

As you probably know, Carson was the host of  NBC's late-night talk show, The Tonight Show, from 1962 until 1992. "The Tonight Show Starring Johnny Carson," as the program was called during his run, made NBC a lot of money --- it was widely reported as among the most profitable shows in all of television in the early-to-mid 1970s, and likely led the list. NBC aired a new episode of the show every weeknight and then ran a "Best of Carson" re-run on one of the weekend evenings (local affiliates were allowed to choose which night), effectively filling up the programming calendar from 11:30 pm until 1 am the next day, six days a week.

Carson himself, though, wasn't a big fan of that weekend re-run. He wasn't against re-running an old episode -- hardly -- he just didn't like the idea that it was happening on the weekend. Producing something new every day, five days a week, is hard work in the media world (trust me), and Carson wanted to be able to take one day off during the normal Monday through Friday workweek. So, as Looper reported, "he told NBC he'd only make four new shows each week, moving 'The Best of Carson' to a weeknight." And Carson had all the leverage, so the network agreed.

"The Best of Carson," though, was a great fit for late-night weekend programming -- it cost almost nothing to make, and the time slot wasn't one that was drawing enough viewers to warrant a major investment in original programming. But the network still needed to fill the 90 minutes that Carson caused them to vacate, and per the AV Club, Carson's coup "reignited the daydream some at the network had of colonizing that patch of broadcast real estate with original programming" -- they just needed to do it on the cheap. Sketch comedy was inexpensive, and live TV -- which doesn't require rounds and rounds of editing -- was similarly less expensive than highly-produced shows. So, as Salon explained, "NBC president Herbert Schlosser and vice president of late-night programming Dick Ebersol tapped Lorne Michaels, a veteran of Rowan and Martin’s 'Laugh-In,' to create something edgy and new."

The end result: Saturday Night Live. The show gained a cult following after its very first episode and quickly became a mainstream hit as well. Carson, however, was not a fan: per Looper, he found SNL to be "crude and sophomoric." He never appeared on the show (but was parodied on it) -- but at least he got to take more vacation time.