It’s one of the most widespread memes of our time — a GIF panning in on an affable-looking bearded man gently nodding in approval.

As few knew the source of the viral clip, many on the internet — apparently born just yesterday — had speculated that the origin was some deep-cut scene featuring comedian Zach Galifianakis. But a closer look reveals that the footage is grainy and dated, by more than 45 years in fact, from a film released when Galifianakis, 49, was just a toddler.

It turns out the warm, wooly meme man is no comedian but legendary actor and certifiable Hollywood hunk Robert Redford, 82, from the 1972 film “Jeremiah Johnson,” about a man who takes to the woods a la Henry David Thoreau on Walden Pond.

The website Know Your Meme reveals that the GIF has been circulating via online message boards since 2012. Then, the following year, viral content website Mashable produced an article identifying the sources of popular GIFs, which included Redford’s nod.

Since then, though, many of the internet’s youngsters had ignored this fact until Splinter writer Nick Martin shared his personal revelation in learning the meme’s true creator. His article went viral on Twitter, where users echoed Martin’s surprise.

“I just found out that this gif is Robert Redford and I am shooketh,” said Stephanie Snowden, a director at The Ringer.

“I will not accept that this isn’t Zach Galifinakis,” wrote @HaoreTom on the social media platform.

Later, @HaoreTom added, “I tweeted this then went to bed and woke up covered in a swarm of angry boomers.”

Meanwhile, many on Twitter, who are obviously of a legal drinking age, expressed their disappointment over the internet’s general lack of diligent observation.

“Anyone that didn’t know this is Robert Redford – or worse, thought it was f-ing Zach Gallifanakis …,” tweeted Arnold Blumberg, a pop culture book publisher “I can’t. I just can’t with you. Jeez, honestly people. Things existed before 2009.”

“There were, in fact, movies made before 2002 people,” quipped @SamRossiOH.

And, in a clever use of the meme, @estevcz responds to the question, “Did you know the nodding meme guy is Robert Redford?” with the GIF itself — demonstrating that, yes, they are a learned person who knows a Redford when they see one.

Even Martin’s colleague could not fathom his shallow knowledge of American cinema.

“Today I learned a not insignificant number of my colleagues never knew Robert Redford is the ‘nodding guy meme.’ Deeply disturbing,” remarked Splinter editor Katherine Krueger.

Of course, Galifianakis is not the only celeb mistaken for the beloved meme.

Joked @mikeleffingwell, “Just found out that ‘nodding meme guy’ is Robert Redford, not Bruce Vilanch.”