Despite its status as one of the most successful and original sci-fi series of all time, Star Wars simply wouldn't be the same without Dune. Although George Lucas' epic space opera changed the game for the genre, it's clear that the series took serious inspiration from Frank Herbert's celebrated novel. As a result, it's not unreasonable to say that without Dune there would be no Star Wars as it exists today.

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Perhaps the most obvious similarity between the two is the setting. Dune's defining feature is the harsh, arid environment of Arrakis, which boasts oceans of sand in place of actual water. By contrast, Tattoine seems to have a slightly more prosperous population and natural resources, but the physical and climatological similarities between the two planets are uncanny. Additionally, one of Tatooine's most famous characteristics is the twin suns that illuminate the horizon. While Arrakis only orbits a single star, it does have two prominent moons, which may have influenced Lucas' thinking about Tatooine.

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Both Dune and Star Wars boast an array of incredible and terrifying creatures. However, none are perhaps more iconic than Arrakis' gigantic sandworms, which can grow to several hundreds of meters long and are even used as a means of transportation by the planet's local Fremen people. Although there are no direct equivalents in the Star Wars universe, the sandworms do share some characteristics with the infamous Sarlacc pit from the Return of the Jedi. Although the Sarlacc's complete physiology is never fully revealed, the creature's sharp teeth bear a striking resemblance to those of the sandworms, from which the Fremen make their fabled Kris knives. To make the comparison even more concrete, the Sarlacc itself even lives in a region of Tatooine known as the Dune Sea.

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One of the most important plot points in Dune is the so-called spice melange, a mind-altering substance that allows for interstellar travel and that's only known source – at least in the first book – is the planet Arrakis. Possession of the spice influences everything in the world of Dune and is one of the factors that shapes the Harkonnen/Atreides feud at the center of the narrative. Although the spice of Star Wars is not as significant to the overall plot as the spice of Arrakis, George Lucas' films do feature so-called spice mines on the planet Kessel, highlighting a clear connection between the two works.

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Living out on the rural sandflats of Tatooine, Owen Lars worked as a moisture farmer in the original Star Wars movie – ably assisted by his nephew, Luke Skywalker, and – for a limited period – the droids R2-D2 and C-3PO. Although Lars' profession initially seems like fairly innocuous backstory, it is actually another example of the link between the franchise and Dune. On Arrakis, devices known as dew collectors allow the inhabitants to harvest water – fulfilling almost exactly the same function as the moisture farmers of Tatooine.

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In Star Wars, the Empire serves as the clear antagonists of the story, subjugating planets and weeding out dissenters. However, although they remain one of the most iconic villains in cinematic history, the Empire owes a clear debt to Dune's Imperium. As the center of political power in the galaxy, the Imperium is arguably a slightly more morally ambiguous presence than the obviously evil empire. However, the Padashar Emperor's clear ambition and aggression towards the novel's protagonists firmly places them in opposition – much like Star Wars' Galactic Empire.

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Both Star Wars and Dune feature guerilla warbands fighting for freedom from the oppression of an imperialist incursion. However, while the Rebel Alliance owes a clear debt to Dune's Fremen, there are differences between the two. For instance, Star Wars' rebels are drawn from all corners of the galaxy, whereas Dune's initially hail entirely from Arrakis. Nevertheless, the presence of freedom fighters in both works provides another unmistakable connection.

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Not only do both Star Wars and Dune feature an oppressive empire, but both versions also boast their own crack troops. Although the fighting abilities of Star Wars' stormtroopers have been much-debated, what is undeniable is that they share some clear similarities with the Imperium's Sardaukar. Both sets of soldiers are supposed to represent an elite fighting force that is feared throughout the galaxy. Although the two designs are quite different, there can be no doubt the stormtrooper concept owes a debt to Dune.

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Carrie Fisher's Princess Leia is one of the most significant characters in the entire Star Wars story, driving the narrative throughout. Although her role as a strong and iconic rebel leader is unquestionable, it's also clear that there are undoubted similarities between her character and Dune's Alia Atreides. The younger sibling of main protagonist Paul – which, in and of itself, suggests another Star Wars connection thanks to Luke and Leia's familial bond – Alia is a mysterious character, blessed with preternatural insight and mind control abilities thanks to her exposure to the Water of Life. Similarly, Leia is not only a close relation of the main Star Wars protagonist Luke, but is also Force-sensitive, suggesting that the link between Leia and Alia is more than just etymological.

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