Men have equaled dongs with power since the dawn of time, and Henry simply found a convenient way to display that power in public without being classified as a sex offender.

"I don't care if my arms look comically undersized. Just make sure my boner is showing."

If you think we're joking, remember that Henry VIII was the man who changed the religion of an entire country to satisfy his penis -- Henry's might very well be the single most influential set of genitalia in history. Though his beloved codpieces eventually went by the wayside, by then, pants had been established as a symbol of power. Everywhere in Europe, men were donning breeches on a daily basis.

Or almost everywhere ...

To be fair, fashion wasn't the only thing they were behind on: Though Russia's territory was massive, its population was pretty small and mostly comprised of farmers, with only a small fraction of all Russians living in towns. Czar Peter the Great decided he had enough of that crap. Peter was obsessed with modernizing Russia, and he started by forcing everyone to put some real trousers on. In 1701, he issued a decree commanding everyone at every level of society to wear pants, other than clergy and peasant farmers.

That meant no more long cloaks or ... whatever the hell that guy in the picture is wearing. Peter also decreed that men could no longer sport beards unless they were willing to pay a yearly beard tax (mustaches were free as long as you kept them under control). Suddenly, Russian men were forced to wear leggings and shave their facial hair at all times, despite Russia's harsh climate.

At this point, evolution granted them Robert Plant hair to protect them from the elements.

Peter the Great's Western-influenced reforms, which also involved completely reorganizing the army, culminated in 1721 when he declared himself Emperor of All the Russians, launching an empire that lasted until the Soviet Revolution of 1917. And it all started with pants.

Peter, seen here basking in the glory of his pants.

So, by the mid-1700s you have a clear pattern: pants are regarded as a sign that your people are modern and civilized. From Henry VIII establishing them as a symbol of power and dominance, to Peter the Great seeing them as a symbol of modernity, the pants revolution was sweeping the world.

Which brings us to one of the last hold-outs after the Russians were pantsified -- these guys:

The Sons of Scotland

The Scottish Highlanders.

As ridiculous as man-dresses may look to us today, back in 18th century, Scotland kilts were seen as an unmistakable sign of badassery and rebellion. The Jacobite Rebels fighting to put a Catholic monarch back on the throne even adopted kilts as an informal military uniform. In 1745, these ventilated-crotch warriors kicked ass all the way into England before they were forced to retreat. Needless to say, the whole thing left King George II feeling a little worried. And so, the following year King George decided that the best way to deal with the Scottish rebels was to take away their kilts. And replace them with pants.

"This last part is very important." - King George II

The punishments for disobeying the Dress Act were severe. If a man was caught wearing anything resembling a dress, he was sent prison for six months. Do it again, and they were shipped off to work on a plantation for seven years. For wearing a kilt.

The only ones exempt from the clothing restrictions were Scottish army officials, who were thus seen even more manly because of it.

"Good Lord! His penis is shaped like a sword!"

By the time the Dress Act was repealed in 1782, the damage was already done. Apparently, men in Scotland had gotten used to the extra support of a good pair of trousers, because even though kilts were no longer forbidden, they continued wearing pants. Maybe they realized that too much freedom can be a bad thing too (especially regarding one's balls), or maybe it was the fact that suddenly all the nobles were trying to bring the kilt back, making it profoundly uncool for regular people. Whatever the reason, traditional Highland garb has gone the way of the codpiece.

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Not that it didn't put up a valiant fight.

The real impact of the Kilt Proscription was its influence on the way that leaders have come to view certain styles of dress as a symbol of rebellion. So, fast forward to the late 1700s, when monarchies were falling and democracy was blossoming. Sure enough, you find pants were right at the heart of it.

This does not mean they fought in the nude. The name was actually a roundabout, somewhat misleading way of saying that the revolutionaries wore long pants, as opposed to the knee-length ones worn by the Royalists.

"Unhand me, you full-panted beast!"

Soon, the Sans-culottes became a symbol of freedom and patriotism -- as did their trousers. After the Revolution, long pants were worn by men of all social strata as a sign of compliance with the new government. The art world started reflecting their popularity, painting the Sans-culottes as ordinary men willing to risk their lives for liberty.

Albeit in a casual, indifferent way.

The artwork depicting heroic soldiers in long pants influenced the kinds of idealized political posters and advertisements we see today. The image of the Sans-culottes has become so ingrained in the modern consciousness that trousers that go down to your shoes are still the only acceptable way for men to wear them. The Sans-culottes effectively erased the manliness of the knee-length breeches (baseball players notwithstanding).

Sans-Culottes established fashion (and more specifically, pants) as a legitimate form of patriotism. So the next time you see a guy wearing a pair of American flag pants, let him know that he has the French to thank for them.

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We're sure he'll be thrilled to hear it.

By the 1930s, starlets like Katherine Hepburn and Marlene Dietrich openly wore pants for comfort and style, but this wasn't really an option for most women. It was the 1930s equivalent of Lady Gaga wearing a meat dress or something. Except crazier. Outside of a few brave souls, women continued to stay away from pants. The taboo was strong enough that nothing short of a worldwide war would change it.

Fortunately, it was the 1930s.

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"What's this about Germany ...?"

World War II changed everything. When women entered the workforce, they did so in their husband's pants. Pants were once again seen as a symbol of patriotism, this time in the form of sacrificing silk dresses so the men could have parachutes. When the war was over most women went back to wearing dresses, but trousers became increasingly associated with working women and the Feminist Movement.

It wasn't until the 1970s that pants became a fully accepted choice for women. One major factor was Title IX, which prohibited educational institutions from discriminating on the basis of sex, meaning that colleges could no longer kick women out for wearing pants.

How could kids possibly concentrate with this waving around in their faces?

In the same year (1972), Helen Reddy recorded the song "I Am Woman, Hear Me Roar," which became a rallying cry for second wave feminists. Reddy became an icon and regularly stood toe-to-toe with the men in an ultra-hip pair of trousers. She was so devoted to pants that she even changed history by appearing as a woman sporting bell bottoms in 19th century Maine in Disney's Peter Dragon.

Her character was secretly a time traveler.

But despite the ridiculousness of the image, these trousers signified that Reddy's character was a tough, independent woman. The same was happening all over the world. Pants had come full circle as a power symbol that once gave men a convenient way to exaggerate the size of their dicks.

Seriously, pants should have their own holiday. Or at least some kind of monument or something.

For more unusual world-changers, check out 6 Mistranslations That Changed The World and 5 Horrible Diseases That Changed The World (For the Better).