While it makes total sense for Disney Plus to relive the phrase when it comes to looking back on the life of Ewan McGregor’s Obi-Wan Kenobi, since his story is inextricably tied to the authoritarian order, the scene is so famous that it arguably stands on its own as one of the great turning points in the Star Wars universe.

As we previously alluded to, Order 66 was essentially Sidious making full-circle his coup of overthrowing the ruling power and placing it into solely his authoritarian hands by ordering the mass execution of its main protectors, the Jedi. As Wookiepedia stated, Order 66, aka Clone Protocol 66, “was a top-secret order identifying all Jedi as traitors to the Galactic Republic and, therefore, subject to summary execution by the Grand Army of the Republic.”

The actual scene in question in which Sidious utters the now-famous phrase happens a little over the halfway mark in Stars Wars Episode III: Revenge of the Sith. Shortly after that, Hayden Christensen’s Anakin Skywalker, having just been re-dubbed Darth Vader after slaying Samuel L. Jackson’s Mace Windu, goes and massacres the “younglings,” aka the Jedi-in-training known as padawans.

Perhaps writer-director George Lucas explained it best on the Revenge of the Sith Blu-ray commentary track about the significance of Order 66 in the story.

The telling of this story, of Anakin going into the Jedi Temple and the other Jedi getting killed through the Order 66 of the clones is just done as kind of one of those inevitable pay-offs in terms of getting rid of everybody. The Emperor that’s getting rid of all his enemies. But there’s a certain inevitability about it all and a sadness to it.

Lucas also revealed in that same commentary track that he was worried perhaps too many plot points were given away in Star Wars: Episode II — Attack of the Clones, to where people may have already guessed the clone troopers would betray the Jedi in the third film. That has everything to do with Christopher Lee’s Count Dooku and his dark side alter-ego, Darth Tyranus.

‘Cause if you go back, they mention the fact that Lord Tyranus and Count Dooku are the same person. You know, Darth Tyranus. And that Darth Tyranus is the one who started the clones. So if you were paying attention, it was very easy to figure out what’s going to happen to the clones, I mean, if they’re going to be the ones to betray everybody. Tough to put in things like that without giving everything away.

There’s actually quite a bit to unpack with just the initial scene of when Sidious is communicating to one of his clone troopers, Temuera Morrison’s Commander Cody, via a long-distance hologram call. While Cody and the other clone troopers were once the allies of Jedi, they soon betray them after getting Order 66 from Sidious.

Order 66 is a fairly important moment in the film, one that producer Rick McCallum called a “turning point” and “a great moment in the picture,” per the movie’s commentary track. However, it almost kicked off in a somewhat silly manner by featuring something of a Russian-nesting doll-like visual gag with the holograms. As visual effects supervisor John Knoll noted in the commentary track,

So originally, there was a whole question about should there be a hologram inside a hologram? Hologram of Cody with his hand out, should there be another little Palpatine there? And we did a version like that and then George decided, no, it’d be better if it didn’t re-transmit.

To show you what we’re talking about, here’s a visualization we mocked up of how the scene almost looked, according to Knoll’s description.

After that initial scene of Sidious giving the order to Cody commences, we are treated to a montage of clone troopers on various planets shooting down different Jedi who are caught completely unaware they’ve been betrayed.

It all culminates in Anakin’s famous scene of massacring younglings, which we don’t see directly, but mostly ascertain through the build-up and aftermath via security hologram footage.

Lucas explained that while the scene was extremely harrowing, it was necessary to include for Anakin’s character development, and ultimate turn to the dark side.

The thing with the kids was very necessary to establish how far down the road he’d come to do something this brutal and barbaric. And it had to be in there but I definitely didn’t want to show it.

Lucas added that the scene in question was intercut with that of Natalie Portman’s Padmé worrying about her love, Anakin, just as we are seeing him “where he’s at his very worst.”

That juxtaposition works quite well ‘cause it reflects as much on the slaughter of the children as it does on her concern about him. Even though she doesn’t know that the children are being slaughtered. But it gives you this very strong emotional connection when those two sequences are pushed up against each other.

By the way, there’s a lot of speculation online that McGregor could not contain his laughter — and so covered his mouth with his hand — after uttering Lucas’ arguably stiffly written dialogue and having to say, “killing younglings” to Padmé, when he later explains the situation to her, as Looper pointed out, but we digress.

After many of the Jedi are killed, there’s also a scene where Yoda can feel the disturbance in the Force caused by this and he clutches his heart briefly and almost loses his balance. That was a scene McCallum called “a very powerful moment.”

Further on in the movie, Emperor Palpatine, aka Darth Sidious, makes a grandiose speech at the Senate which is when the democratic union of the Galactic Republic officially dissolves and the authoritarian Galactic Empire is born to take its place. This “birth” scene intercut with another scene of Anakin slaying adult Jedi at a command station — and thus fulfilling Order 66 to completion — was Lucas’ nod to Francis Ford Coppola’s The Godfather.

This is where, in The Godfather, he’s doing the christening of the baby and at the same time killing all of his enemies. And that’s kind of what’s going on here … is the Emperor is declaring the Empire at the same time he’s wiping out the last of his allies, really. It’s contrasting those two events against each other.

Although many Jedi died as a result of Order 66, not all of them did. For instance, Obi-Wan Kenobi and Yoda would later appear in episodes IV-VI, aka the original Star Wars trilogy, so we know they survived, among others. As we know from an appearance by Rosario Dawson in The Mandalorian, Jedi Ahsoka Tano, Anakin’s former apprentice, also survived Order 66.

In terms of the clone troopers’ compliance with the Order 66 Protocol, that was actually baked into the mass manufacturing process for them using a chip. As Wookiepedia explained,

All clones were given a behavioral modification biochip that could be activated by remote order via voice command […] The biochip, when activated, would ensure total obedience in a clone, erasing existing biases and beliefs and instilling absolute loyalty to Palpatine.

Lucas also said on the commentary track that though Star Wars was written a long time ago, “it was based on history” and was always “reasonably political,” but that Revenge of the Sith is just a film that stands out even more in that regard.

In fact, although the samurai of feudal Japan are often pointed to as a major influence for the Jedi, the medieval Knights Templar of the west may have also been a major inspiration, according to History. In fact, there was even a mass execution of the knights commissioned by the King of France at one point that largely resembled Order 66. The article explained,

Much like the Great Jedi Purge ordered by Chancellor Palpatine in Revenge of the Sith, France’s King Philip IV annihilated the Knights Templar after arresting hundreds of them on October 13, 1307, and subsequently torturing and executing them for heresy.

There’s also a long-running fan theory that the name of Order 66 intentionally resembles the U.S. Executive Order 9066, which is an executive order that President Franklin Delano Roosevelt made after the Pearl Harbor bombing in World War II. The directive ordered the mass incarceration of Japanese-Americans into internment camps based solely on ethnic heritage. This connection was proposed by the Reddit user u/misterbristles on the r/StarWars subreddit, among other fan theory sites.

“[I]t doesn’t have that much in common with Order 66 apart from the title, but, I dunno, I just kinda have this odd feeling about it,” the fan wrote, citing other connections Lucas has explicitly made about Star Wars and WWII.