The 5 Most Terrifying Civilizations In The History of the World

5 The Celts

History is kind of spotty on the Celts (they never wrote anything down, and many of the witnesses died brutally) but what facts survived confirm one thing: They had gigantic Celtic balls.

First of all, they had a thing for severed heads. After a long and trying battle they'd all unwind at the end of the day by collecting a few souvenir heads. Then they'd bring them home and decorate the house with them. So the average Celt home probably looked like a hunter's trophy room, crossed with the scene at the end of Halloween when all the mutilated bodies start popping up around every corner. Sweet dreams kids!

If they felt that yours was a head of particular importance, they'd embalm it and whip it out at parties to brag about how awesome they were. When they were alone they'd probably wiggle your jaw around and pretend you were complimenting them.

The reason for all of these head-chopping-good-times was that the Celts believed that the head held the soul, and so if you cut a dead guy's head off before all of that juicy soul leaked out of it, it was yours. A finders-keepers sort of deal, you might say.

A modern Celt.

So, Were They Really So Bad?

Hey, remember Braveheart? And how batshit insane Wallace's army looked with their faces painted blue?

Well, the Celts would sometimes paint themselves blue and fight completely naked. Just because. One would assume that fighting in the nude would present some rather sensitive targets to one's enemies (we're talking about their nuts), but it seems that the Celts were so frigging manly that they just didn't care. It was the ultimate insult: "I am not afraid of you, and to prove it, I have just laid my dong on your sword."

4 The Aztecs

You remember Temple of Doom, and how that unfortunate gentleman had his heart ripped out right before they dropped him down the lava hole? Well, picture lots of that, only this time mom isn't around to turn off the VCR and stop your crying. That's the Aztecs.

The Aztecs believed that for every 52 years that passed, the world would end unless the gods were strong enough. And, as is common knowledge, the best way to toughen up a god is with a steady stream of constant human sacrifice (along with a dash of cannibalism, just for good measure).

Most of the sacrificing went towards keeping their Sun god happy, and it took place on top of giant pyramid, so at least the view was probably pretty good. Then they'd hold you down, saw through your ribs and take out your heart (which was likely still beating). Then, as if things couldn't get any worse, they'd throw you down the staircase.

So, Were They Really So Bad?

Yes. Yes they were. Did we mention the cannibalism? After they removed your heart and threw you down the stairs, they'd eat your arms and thighs, and whatever other bits looked tasty (the nuts? We do not know).

Some historians think that nourishment was the main reason behind all of this willy-nilly human sacrifice, as the Aztecs had no domesticated animals to slaughter, and as such their diet was low in fat and animal-stuff. You know how it is if you've ever had a roommate try a vegetarian diet. It's just a matter of time until you start waking up with teeth marks on your extremities.

And that's not even the bad part. The Aztecs held themselves to a high standard and for every situation they asked, "Could we make this more gut-wrenchingly gruesome?" So, for instance, during the sacrifice to the fire god, a newly-wed couple would be tossed into, you guessed it, a fire. Then, right before they finally died (from their horrendous burns), they'd drag them out, flesh still smoking, and dig out their hearts.

Wait, it gets better! There was the offering to the earth goddess, which involved a young woman's skin being removed and worn around like a Silence of the Lambs-style serial killer flesh suit.

On one hand you might ask why none of the Aztecs thought this was odd. On the other hand, if somebody had an objection to the ceremonies we're guessing they kept that shit to themselves.

3 The Assyrians

The thing about the Assyrians is that they were basically the ancient Mesopotamian equivalent to that loveable team of underdogs in every sports movie. They had a lot of spunk and a can-do attitude, but, try as they might, they just couldn't seem to make it into the big leagues.

Luckily for them (and unluckily for everyone else), just as that loveable sports team will sooner or later stumble upon secret weapon, a magic dog with an unusual aptitude for kicking field goals perhaps, after a couple of hundred years of being constantly harassed by more powerful nations, the Assyrians came across their own secret weapon. No, it wasn't Emilio Estevez, but it was nearly as powerful.

It was iron. The Assyrians were the first people to start using iron weapons instead of bronze which, to put into a modern perspective, is sort of like showing up for a knife fight with the Death Star. Using iron made the Assyrians so near-invincible that, really, the other guys might as well have been swinging around bananas.

So, Were They Really So Bad?

Well, in a word, yes. Here's a cheery little quote from King Ashurnasirpal, who spent much of his spare time baking cherry pies for the homeless and teaching the neighborhood kids how to correctly adjust their bike helmets:

"I built a pillar over against his city gate, and I flayed all the chief men who had revolted, and I covered the pillar with their skins; some I walled up within the pillar, some I impaled upon the pillar on stakes, and others I bound to stakes round the about the pillar; many within the border of my own land I flayed, and I spread their skins upon the walls; and I cut off the limbs of the officers, of the royal officers who had rebelled."

"And then I was thinking about slap boxing with a lion, but only if there's time."

Ever have one of those days when you just wanted to get out of the house and flay somebody? Yep, you're probably a sociopath.

Sure, we understand that intimidation was how invading armies ended wars before they started, that this kind of psychological warfare was crucial for a conquering army. But reading that up there, we're pretty sure the Assyrians just enjoyed it.

2 The Spartans

All it took was one movie, and now everybody knows the ancient Spartans weren't the kind of guys you'd want to invite to your fancy cheese-tasting party. They'd probably stumble in, mock you for not being a full-time member of the military, then impale all of your guests with spears. Not to mention they'd eat all your fancy cheeses.

And you know what? It wasn't just a movie. That thing at the beginning of 300 where they'd toss all imperfect babies off the cliff, letting them splatter on the rocks below? They really did that. But first they would bathe the newborn in wine, to see if it was strong enough to survive. That's right; being a Spartan meant you had to handle your damned liquor right out of the damned womb.

So, Were They Really So Bad?

Every single Spartan male was a soldier. Every other job was done by slaves; the Spartan men were warriors and that was that. They fought until they could finally retire at the age of 60 (about the equivalent of living to 400 years old today).

Of course if you lived to be that ripe old age, were a good father and scholar and all-around great guy, too bad. You didn't even get a headstone when you died, you didn't deserve it. The only Spartans who got marked headstones were the ones who died in battle, during victory. Think you're a war hero? Well, if you're still alive that meant you still weren't hero enough for Sparta.

Look at how alive they all are. Pathetic.

Oh, and if you lost your shield during battle, you got the death penalty. A true soldier would have gone back to get it, or died trying.

If we (or the movie) make them sound like heroes, well you have to know about those slaves we mentioned earlier. The Spartans beat their slaves... by law. We don't mean the law allowed them to beat the slaves, we mean the law required it.

Things could get a lot worse for slaves, though. As a sort of coming of age holiday, there was an occasion every year upon which the young Spartan men were encouraged to sneak around and murder as many slaves as they could, without having to feel bad about it. If you didn't murder anybody, they probably called you gay.

1 The Mongols

Now imagine 400 of those stadiums, each full of people. Now imagine every single one of those people with grotesque stab wounds.

That's right; it is estimated that the Mongols--under Genghis Khan and others-- killed 40 million people.

With swords.

The Mongols ripped through the world like a lawnmower. They were like an army of Batman villains. Only Asian, and on horseback.

Even the horses look pissed.

When the Mongols got in a conquesty mood, if your town happened to be in the way, you were, as they say, "shit out of luck." The Mongols would give you two choices, both of which thoroughly sucked. The first, and most practical, was to surrender and let them take whatever they wanted (which was pretty much everything, likely including your livelihood and all the women-folk). The second choice was to not surrender, and thus promptly watch your town burn to the ground. And your fields salted. Then, just to add another scoop of crap to an already crappy day, you'd be brutally murdered.

So, Were They Really So Bad?

During an invasion of India, a Mongolian general built a pyramid in front of the walls of Delhi out of human heads. Are you picturing it? If so, are you picturing like two dozen heads there? Because this guy used 90,000 of them.

They, like the Celts, had a thing for severed heads. They liked to gather them up and catapult them inside the enemy's compound. They would also fling corpses infected with black death.

"You know, most invading hordes just use arrows."

When they ran across pregnant women, they did... things. Things we won't discuss here.

When you saw them coming, hey, you could shoot at them with your arrows and spears all you wanted. All you'd be doing is slaughtering the huge crowd of refugees the Mongols forced to march ahead of them as human shields.

So, yeah. You want to know why the Spartans have to settle for number two, that's fucking why.

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