DUNE is a bit of a special interest of mine. So I will thoroughly enjoy this exercise, as I have a 9 year old, but I'll aim for a 5 year old.

Backstory isn't really relavant to Frank Herbert's novels, but it is a fun one.

Humans have gotten really good with computers. So good, that they now attempt to make computers do their thinking for them. Some humans thought this would make their lives easier. Except it only allowed other humans with thinking computers to enslave them, and it lead to a big war.

The war ended up being between the thinking computers and last humans. We already had the ability to travel between stars, but it takes a long time. A really smart woman invented a technology that allowed protection from pew pews, and the ability to travel through space instantly.

The thinking machines didn't have the technology. The only problem was that when the space ships used it to travel space instantly, a lot of the ships blew up because they couldn't see exacrlt where the ship would travel.

The smart woman found that a new medicine, taken from the sands of the planet Dune, let her see all possibilities, briefly into the future. This allowed the ships to travel instantly. This helped the humans defeat the thinking machines.

After the war, humans decided that computers were very bad. So they created schools to train some people in ways to replace computers. Mentats were very good at math, had a lot of knowledge, and excellent problem solving ability. Suk doctors were able to do everything that machines used to be required to cure people. The Bene Gesserit were to help shape humanity to prevent stagnation and enforce the ban on computers.

The space ship pilots controlled the who universe though. And since the medicine they needed came from Dune, all the power of the universe was sitting in that single planet.

Far in the future, humanity is spread across space in a vast empire.

Long before the events of the book, humanity fought a long and bloody war against computers aka "thinking machines" which led to the destruction of all computers and a total ban on them.

Luckily there exists a substance called "spice" which enhances the human mind to incredible levels, allowing human brains to do everything from complex mathematical calculations to plotting courses for space flight. It's only because of spice that computerless society and interstellar travel are able to exist.

Spice has a drawback, though: it's incurably addictive.

It's also only found on one planet, called Arrakis or Dune. As you can imagine, this makes Arrakis a strategically critical planet.

There are tons of other social, political, and religious details to the universe but this is the basic premise.

It takes multiple books to cover, so this is the very, very basics:

~12,000 years in our future, Humanity goes to war with "thinking machines." The war lasted a while, humans finally win, and vowed to never create such machines again. Another ~12,000 years later, Dune takes place.

By this time, the "no AI/computers" is such a deeply ingrained belief, that it has made its way into literally every facet of culture: politics, religion, commerce/transportation, etc. Of course, having fast calculations is also really handy, so humans resort to selective breeding programs and strict social castes that result in human calculators (Mentats) and other specialized professions. Even that's not good enough to do interstellar travel calculations, so some people are imbued with "spice" (discovered on one planet, Arrakis, the Dune planet).

It's basically space magic mushrooms. Opens the mind like nothing else. That's the only way to do interstellar commerce, so it's the most valuable commodity in the galaxy, and whoever controls the planet gets enormously powerful, and also has a huge target on their back. Meanwhile, a maternal religious sect is running its own breeding program to get to fulfill some "chosen one" prophecy.

Thinking robots almost destroy humanity, then awhile later Space Jesus defeats space fascists then goes on to destroy most of the settled universe in a crusade of destruction.

Also for kicks a one sentence summary of the foundation series: mathematicians reduce the time between civilization collapses by predicting the behaviors of large groups & settling remote outposts to restore order, but an unpredictable very powerful individual changes the plan.

Magic space dust that makes warp drive work only exists on Giant Worm Planet. Warp drive only works when one of the mysterious navigators eats some, allowing them to "travel without traveling". (Hint, they're giant space worms, I can't remember if this is revealed early in the books or not, but it's right at the start in the movies).

Space Nazis in charge of worm planet made their emperor mad, so he gave the planet to a different clan.

Space Nazis hated that, so they attempt to sabotage the planet handover.

So do the natives of worm planet.

So do the worms of worm planet.

Worm planet natives win with the help of the "prince" of the clan that took over. Prince of that new clan earns the respect of, and becomes the leader of, the worm planet natives, who collectively fight off the emperor and the space Nazi's combined forces at the end of book 1.

At the start of Book 2 (12 year time skip) the pince is the emperor of the known universe.

At some point after this he space prince's son turns into a worm.

I’m going to get most of this wrong, but here’s the jist:

Ancient history

• Humans colonize the stars (probably a couple hundred years from us today). We use tehcnology not much different than us today: computers and rocket ships. It works, but it’s very slow when compared to the vastness of space.
• After about 2 thousand of years of slowly expanding our reach into the galaxy, there are thousands of colonized planets and Earth just doesn’t matter. It fades into lost history.
• Technology evolves and at some point AI computers try to take over the galaxy. Humans fight back and win. At this point, “thinking computers” are banned across the galaxy

Newer but still kind of ancient

• There are great Houses, or ruling families, that arose on different planets. Many claimed control over entire systems of planets.
• After the thinking machines were banished, one great House claimed the galaxy as its Empire. The rest of the great Houses formed a parliament of sorts, called the Lansarad. The Emporer and the Lansarad keep balance each other’s power
• There are literally hundreds of thousands of colonized planets at this point. Entire populations drift genetically. Everyone is still human, but entire populations will look very, very different from others.
• There are also many factions at play, other than the ruling houses. One notable faction is a women’s only order called the Beni Geserit. They acquire many abilities that are super human, like glimpsing the future, forcing people to speak only truth, and forcing weaker people to perform actions simply by speaking to them.
• some humans, called mentats, fill in the space left behind by thinking computers. They train on the ability to perform extreme calculations in their heads
• another faction that arises is the Spacing Guild. After old school technology receded, due to no thinking computers, they claimed the only way to perform interstellar travel. THEY ARE VERY NEUTRAL. They do not give a damn about two warring factions. You do not fuck with the spacing guild because they will ban your entire people from off world travel. If you are at war with the person next to you on your interstellar voyage, you set aside your differences during that trip.

“Now”

• it’s been 10 thousand years since thinking computers have been banished.
• there is a planet, named Dune…. Actually that’s the nick name. The real name is Arakis. But loaded of people call it dune because it’s just a giant planet of sand. …and Spice
• spice is only found on dune. And it’s the key ingredient for the spacing guild’s interstellar traveling.
• the emporer owns the planet, but assigns one of the great houses to run operations.
• side note, the spacing guild is so neutral, even the emporer doesn’t fuck with them. He owns Dune, but is more or less obligated to sell to the spacing guild less he lose his traveling permissions
• but the spice does lots of things. It grants some of the same special abilities the Beni Geserits have. I’m pretty sure they use the spice to gain their powers.

Dune, the story

• lots of factions with long term goals. And by long term, I mean plans that take thousands of years to achieve.
• each faction is essentially just boiling down to trying to control the universe, save for different ways of doing this. It usually boils down further to “if I can just control dune/the spice…”
• its messy, lots of back stabbing
• most of the story takes place on dune, the planet. But characters are all around the galaxy are acting in ways of great impact.

150,000 years into the future, some kid puts a bunch of worms on his skin, becomes God Emperor of the universe, and makes infinite clones of Jason Mamoa so they can bro out until one inevitably kills the other, at which point they start over.

Other stuff happens but that's the important part.

It's a love story, really.

The planet Dune is special, because only there Spice, the most important chemical in the universe, is found.

Several noble families and organizations battle to gain control over the Spice.

---SPOILERS below for parts 1 & 2 of the series---

One of the families is set up to be murdered, but their young son survives. He is rescued by the planet's locals.

These locals are fierce, and they are many.

---SPOILERS for part 3 & the rest of the books---

Lead by the noble son, the local people rise up and conquer the universe. The son becomes the new emperor.

He realizes that the universe – and mankind – is vulnerable because of the single source of Spice. Under the influence of Spice, he sees and enforces a Golden Path, which will eventually ensure mankind's survival but destroy the empire.